Why I am interested in the SD1

[leonard callow]

. . . you do not get, for example, the same image if you down rez to say 100 DPI and then shrink to 8x12 as you get when you shrink to 8x12 @ 300 DPI and then down rez to 100 DPI.

I must be missing something- of course you don't - in the second case your image size will be 3 times the size of the first.

say your image is 4800 x 7200 @ 300dpi- therefor 16" x 24" (@300dpi)

when you change the dpi to 100 the only change is that your image would now be 3 x the size in inches (48" x 72") -IF printed-

but the image is still 4800 x 7200 - it has not changed at all - the only thing that has changed is the instruction to the printer.

if you now say to make it 8" x 12" at 100 dpi - the image will now be reduced to 800 x 1200 pixels. whereas if you downsize to 8" x 12" @ 300 dpi your image will be reduced to 2400 x 3600 pixels which is three times the size. note that if you now were to change to 100 dpi your image does not change in any way - it remains exactly 2400 x 3600 pixels (again ONLY the instructions to the printer have changed)

this is trivial - of course the images are different.

but somehow I don't think this is what you are talking about and I must be missing what you want to convey.

--
Leonard

 

[Walter S Matthews]

. . . you do not get, for example, the same image if you down rez to say 100 DPI and then shrink to 8x12 as you get when you shrink to 8x12 @ 300 DPI and then down rez to 100 DPI.

Maybe I didhn't write it properly although it still looks clear to me

How to take the image from the 645D and make an 8x10 at 100 dpi out of it so that it can be displayed on the net.

You have already written the aspect ratio of the image from the 645D which is is 4x5 and not 4x6. I was making a general statement but since you put in real numbers I'll stick to them

3 ways to do it. Probably more but I have tried three.

1. Set the DPI in "Image Size" in photoshop to 8x12 and the dpi to 100 and you get image 1.

2. Set the DPI to 100 from 300 and you get the 16x20 at 100 dpi. In a second operation resize that 16x20 to 8x10 and you have image #2 which is an 8x10 @ 100 dpi just like #1 However #1 does not look like #2

3. Resize the original 16x20 to an 8x10 at 300 dpi and then take that image and in the second step drop the the dpi to 100 and you get image #3, still a third 8x10 at 100 dpi. There are pretty dramatic differences in the appearances of the three 8x10's that are all at 100 dpi.

At first I thought all I had to do was do it on one image, figure out which was the best iimage and use that method all the time.

Wrong

It apparently depends on what is in the image as to which method is better and I have not figured out yet what in the photo influences it more one way than the other.

I am sure that eventually I will figure it out

 

[Lin Evans]

Hi Walter,

I suspect the SD1 will come close in optical optical resolution, probably not equal though, but even though these are really great crops, there is something going on which I don't like in the very "back" of the hair line on each of these.

I'm uncertain what is causing it, but if you closely examine the hair on the very rear edge of the heads, something's happening which I would be inclined to clone out with a feathered brush. Hopefully, the SD1 will not have this same issue, and perhaps this is only a fluke thing, but not quite up to par in that area of the photo.

Best regards,

Lin
--
learntomakeslidshows.net

 

[Walter S Matthews]

Lin

I have had this problem with niikon glass and with Canon L glass as well, I think it is more of a bright light ibackground illumination problem than any issue with the lenses or detector.

I posted about it above and I'll repeat the words.

When you photograph a subject, person or a group, when the light source is bright, diffuse and directly in back of them, as it was in the group shot i posted that was taken from the deck of the Queen Mary in Long Beach, you get diffraction of light that happens from a solid edge getting in the way of the light source. You can see the phenomenon best when you look at the suns ray with two parallel blinds and you will see that the edges of the blinds are literally bent around the sun. That has nothing to do with the camera or the lens but is a function of the Physics of the situation. In this photo if you look at the top of the hair of both girls youwill see a mess where the light is literally bending around the top and making a mess around the edges. I have encountered this several times in the past and have never really found a solution. I have used flash which does help a little but its pretty hard to offset the effect completely. The best solution is to move the subject to where they don't have that bright halo generating background but you don't always have that option like, in this example. I was not the photographer but one of the people taking photographs and it would not have been polite to ask them to move. The Navy paid a guy to shoot the event and as a guest I just went along.

If you or anyone else can tell me how to get good photos under thest conditions I am happy to learn. I get the problem when it is overcast, the sun is relatively low and in back of the subject making a large diffuse light source directly behind the subject.

 

[DaSonyGuy]

I have had this problem with niikon glass and with Canon L glass as well, I think it is more of a bright light ibackground illumination problem than any issue with the lenses or detector.

I posted about it above and I'll repeat the words.

When you photograph a subject, person or a group, when the light source is bright, diffuse and directly in back of them, as it was in the group shot i posted that was taken from the deck of the Queen Mary in Long Beach, you get diffraction of light that happens from a solid edge getting in the way of the light source. You can see the phenomenon best when you look at the suns ray with two parallel blinds and you will see that the edges of the blinds are literally bent around the sun. That has nothing to do with the camera or the lens but is a function of the Physics of the situation. In this photo if you look at the top of the hair of both girls youwill see a mess where the light is literally bending around the top and making a mess around the edges. I have encountered this several times in the past and have never really found a solution. I have used flash which does help a little but its pretty hard to offset the effect completely. The best solution is to move the subject to where they don't have that bright halo generating background but you don't always have that option like, in this example. I was not the photographer but one of the people taking photographs and it would not have been polite to ask them to move. The Navy paid a guy to shoot the event and as a guest I just went along.

If you or anyone else can tell me how to get good photos under thest conditions I am happy to learn. I get the problem when it is overcast, the sun is relatively low and in back of the subject making a large diffuse light source directly behind the subject.

I cant really understand why you were worried about a few big guys...Its a wedding not a fight club...Everyone will be in a placid mood and therefore more amenable to following the requests of anyone holding a camera. Wedding guests dress their best because they know its the one occasion when they have dispell their normal reserve and let themselves be photographed.

Difficult lighting demands you try a different approach...Being Polite is'nt going to help, its only going to hinder...Be bold. Ask them nicely and chances are they wont mind swinging the group round to a different angle to help you out...Make the pretence that the photo would look much better with this or that behind them. It would only take a few seconds of their time (Well, at least it would with a DSLR...Not so sure about with a Clunky Pentax 645D) and if you end up with better shots than the official wedding photographer/s, all the better to help you sell your shots to them.

--
DSG
--



--
http://sigmasd10.fotopic.net/

 

[D Cox]

"How to take the image from the 645D and make an 8x10 at 100 dpi out of it so that it can be displayed on the net."

dpi is irrelevant for screen displays. dpi is an instruction to the printer driver software.

Go to the image size panel in Photoshop. Make sure "Resample image" and "Constrain proportions" are both checked.

Then set the height of the image in pixels to suit the size of window you want on your screen. On a 1920x1080 screen, this might be around 800 or 900, to allow for some stuff above and below the image. Any bigger and you have to scroll around.

If you want to suit viewers with older, lower resolution monitors, set a smaller number.

dpi has nothing to do with web images. Nor do inches - two monitors can have the same resolution but very different sizes - one could be a computer monitor and the other a big TV.

 

[Walter S Matthews]

Have you ever been the official paid photographer at a wedding?

Its a wedding not a fight club...Everyone will be in a placid mood and therefore more amenable to following the requests of anyone holding a camera.

Difficult lighting demands you try a different approach...Being Polite is'nt going to help, its only going to hinder...Be bold. Ask them nicely and chances are they wont mind swinging the group round to a different angle to help you out...Make the pretence that the photo would look much better with this or that behind them. It would only take a few seconds of their time (Well, at least it would with a DSLR...Not so sure about with a Clunky Pentax 645D) and if you end up with better shots than the official wedding photographer/s, all the better to help you sell your shots to them.

First, it wasn't a wedding. It was an official retirement ceremony of the US Navy, three Admirals and probably a total of 1000 service men of different ranks in attendance. Most of the officers were there with their wives and it seems all the officers wives had digital cameras. I was an invited guest and not the official photographer and there were at least 30 other guests standing around who were also taking essentially the same shot.

If it was a wedding where I was the official photographer and you or anyone else had asked the group that I had set up to please move so that you could get a better shot, I would politely ask you to ...well... I'm not sure what I would do. I would probably cease to be polite at that time and ask you to cease taking photos. If you continued to interrupt I would request of the wedding coordinator that you be asked not to take photos. In over 600 weddings that has never happened to me. I don't mind guests taking photos when I am the official photographer but i would not allow a guest to direct the action.

if you end up with better shots than the official wedding photographer/s, all the better to help you sell your shots to them.

Do you actually photograph groups set up by the paid photographer at a wedding and then try to sell the photographs you have made to the wedding couple?

If this actually happened to me and I had a signed contract with the couple, I think you would see me in court.

 

[Lin Evans]

Walter,

I "think" it might be exacerbated by relevant subject to background distance. If you look carefully at the first image posted (the girl in the red dress), notice that there is a faint "hint" of this between her right side and the background where her skin is close to the backdrop (her latissimus dorsi muscle area). It seems to disappear and not be seen between her arm and the backdrop. The only relevant apparent difference being the distance from the backdrop. Her arm is slightly forward. Oddly, though, it appears on the hair which is backed only by sky. It's not a simple thing. I haven't experienced that myself with any of my systems shooting under similar conditions. I do notice it in single strands of hair as well on the fringes of the those "wispy" strands standing apart from the main body. It might be worth experimenting with a polarized filter to see if it's possible to change it or eliminate it.

Best regards,

Lin

Lin

I have had this problem with niikon glass and with Canon L glass as well, I think it is more of a bright light ibackground illumination problem than any issue with the lenses or detector.

snip

If you or anyone else can tell me how to get good photos under thest conditions I am happy to learn. I get the problem when it is overcast, the sun is relatively low and in back of the subject making a large diffuse light source directly behind the subject.

--
learntomakeslidshows.net

 

[Lin Evans]

Some years ago, we were plagued with a very similar issue with certain Canon lenses. It was a hot topic for some months on the forum here. It was commonly known as PF (Purple Fringe) and there were eventually a number of Photoshop actions which essentially selected the color and treated it on a separate "layer" by desaturating. This, of course, greatly ameliorated the effect but didn't address the cause. Certain cameras such as the Sony F828 were absolutely "guaranteed" to produce it strongly with any high contrast areas such as a bright gray sky behind green leaves on a tree. This issue seems to have been nearly eliminated in more current systems, or at least greatly reduced. There were endless debates on the "cause" but this chromatic aberration was definitely exacerbated with certain lenses. Someone did a very thorough explanation, but I've forgotten which forum - I think in the Canon forum which would now be more difficult to find because of the various sub-divisions for different dSLR's which didn't exist then.

At any rate, you can greatly improve the "appearance" by selecting for the "color' and desaturating.

Best regards,

Lin
--
learntomakeslidshows.net

 

[DaSonyGuy]

Have you ever been the official paid photographer at a wedding?

Yes.

Its a wedding not a fight club...Everyone will be in a placid mood and therefore more amenable to following the requests of anyone holding a camera.

Difficult lighting demands you try a different approach...Being Polite is'nt going to help, its only going to hinder...Be bold. Ask them nicely and chances are they wont mind swinging the group round to a different angle to help you out...Make the pretence that the photo would look much better with this or that behind them. It would only take a few seconds of their time (Well, at least it would with a DSLR...Not so sure about with a Clunky Pentax 645D) and if you end up with better shots than the official wedding photographer/s, all the better to help you sell your shots to them.

First, it wasn't a wedding. It was an official retirement ceremony of the US Navy, three Admirals and probably a total of 1000 service men of different ranks in attendance. Most of the officers were there with their wives and it seems all the officers wives had digital cameras. I was an invited guest and not the official photographer and there were at least 30 other guests standing around who were also taking essentially the same shot.

Ok, that puts a slightly different complexion on things.

If it was a wedding where I was the official photographer and you or anyone else had asked the group that I had set up to please move so that you could get a better shot, I would politely ask you to ...well... I'm not sure what I would do. I would probably cease to be polite at that time and ask you to cease taking photos. If you continued to interrupt I would request of the wedding coordinator that you be asked not to take photos. In over 600 weddings that has never happened to me. I don't mind guests taking photos when I am the official photographer but i would not allow a guest to direct the action.

if you end up with better shots than the official wedding photographer/s, all the better to help you sell your shots to them.

Do you actually photograph groups set up by the paid photographer at a wedding and then try to sell the photographs you have made to the wedding couple?

I have done, yes. I was invited to friends wedding and I took my SD14, three manual focus primes along. (Tokina 17mm f3.5, Pentacon 50mm f1.8 and a M645 80mm f2.8.) and Metz 54mz-3 flashgun. He had paid an elderly husband and wife team, shooting Nikons, £1800 for their services. I just pottered around taking a few snapshots here and there.

A week or so later, me and my newly married friend were viewing their efforts on a special wepage showing a sample of each photo so he could work out which ones to order. A completed wedding photo album ordered from the same couple would have cost another £1800 BTW.
I showed him mine, which I had uploaded to a photohosting site.

He did'nt like the poor quality Nikon samples and wanted mine instead...As he was a freind I got them printed a 7x5 at Jessps and only charged him £120.
He and his wife were happy as larry with the results.

If this actually happened to me and I had a signed contract with the couple, I think you would see me in court.

Well there was one point in the church when the old official photographer threated to leave if I kept taking pictures...I told him "dont let me stop you, theres the door", but then I thought, heck, its my freinds wedding and I dont want to spoil it so I went and sat down...I won out in the end though.

 

[DaSonyGuy]

Some years ago, we were plagued with a very similar issue with certain Canon lenses. It was a hot topic for some months on the forum here. It was commonly known as PF (Purple Fringe) and there were eventually a number of Photoshop actions which essentially selected the color and treated it on a separate "layer" by desaturating. This, of course, greatly ameliorated the effect but didn't address the cause. Certain cameras such as the Sony F828 were absolutely "guaranteed" to produce it strongly with any high contrast areas such as a bright gray sky behind green leaves on a tree. This issue seems to have been nearly eliminated in more current systems, or at least greatly reduced. There were endless debates on the "cause" but this chromatic aberration was definitely exacerbated with certain lenses. Someone did a very thorough explanation, but I've forgotten which forum - I think in the Canon forum which would now be more difficult to find because of the various sub-divisions for different dSLR's which didn't exist then.

At any rate, you can greatly improve the "appearance" by selecting for the "color' and desaturating.

Ultimately, CA is a lens quality issue. Normally CA is most visible at wide apertures, and in most cases it dissapears when you stop down. The better the lens, the less CA you will see at wide apertures. Most modern Aspherical lenses have very low levels of CA, even wide open, because the whole point of an Aspherical element is to allow all colours to focus to the same point...Its much harder to this with older spherical lenses unless you add lots of additional elements, increasing lens complexity and price...Most modern lenses contain at least one Asperical element and its why their performance is often better than older spherical equivalents and why older lenses usually show more CA wide open.

The Sigma 8-16mm ultra wide zoom has three Aspherical elements as well as four "FLD" low dispersion glass elements...A very exotic formula indeed, but it brings dividends because its optical performance is undoughtably first rate. Given its extraordinarily wide focal length the maximum CA for the said lens is only 1 pixel wide!...Hardly noticable even when pixel-peeping at 100%.

 

[Walter S Matthews]

Well there was one point in the church when the old official photographer threated to leave if I kept taking pictures...I told him "dont let me stop you, theres the door", but then I thought, heck, its my freinds wedding and I dont want to spoil it so I went and sat down...I won out in the end though.

No, you did not win out anything.

What you did was immoral and it is illegal

You were completely out of line.

First, you interfeared with the paid professionals ability to get photos by being in the way. Even if you were not standing in his way, you distracted him and your friend and his wife and the guests to the point that the photographer had to ask you to cease and desist. Moreover, the relationship between the photographer and his clients, especially at a wedding, is absolutely critical. The bride is always tense and afraid of how she will look in photos and if you are messing with the chemistry betweeen the photographer and his clients you have crossed a line that no professional would cross.

If you were a professional photographer you would never behave that way.

You were in the way to such an extent that the photographer demanded that you stop. That means the groom and his bride were aware of the conflict and quite literally, you traded on your relationship with your friend to mess with whatever chemistry the photographer had established with the couple. Once the conflict with the photographer had happened in full view of your friend and his bride, the photographer cannot recapture the chemistry with the couple.

You F_ d it up and it cannot be repaired. Of course the couple will take your side because you are a friend.

Wedding photography is not about this pose or that background, it is about the relationship that the photographer has established with the couple and you inserted your self into that relationship and destroyed the most important element of his work. How well he is able to interact with the couple.

Second, you took business away from him by selling your photos to your friend.

Whether you like the equipment selection of the paid professional or not or even whether you liked the photos or not it was theft.. I am certain that you influenced your friend to like your photos more as well.

By the way i have invited many forum members, from another two forums, to shoot with me and so far, 6 forum members have shot with me. The important element there is to shoot with the primary photographer in a way that you enhance each others photos. The object, after all, is to get a good set of photos for the couple. By the way, i always insist that all photos be put into the primary package that the couple gets and they never know which photographer took what shot. It is not a contest, it is an attempt to cover an important event in their lives and you messed with that event and should not have.

You could have worked with the photographer but instead you chose to compete with him.

 

[Lin Evans]

There are numerous types of CA. Typically, lateral and transverse CA are lens issues, but purple fringing (which is also a type of chromatic aberration) can have more than one cause. It can be associated with micro-lenses, flare or even hyper sensitivity of the sensor to certain frequencies. It's not a simple thing and it's been discussed and debated ad infinitum on the forums beginning back in the days of the Canon D60 and extending through the Sony F828 which was notorious for it. There have been multiple theories advanced to account for it, but "most" manufacturers have found solutions. Nikon does it in firmware but it's still seen to some degree in lower end digicams, and not so much in dSLR's. That's why I was surprised to see it on this high-end camera.

Best regards,

Lin

Some years ago, we were plagued with a very similar issue with certain Canon lenses. It was a hot topic for some months on the forum here. It was commonly known as PF (Purple Fringe) and there were eventually a number of Photoshop actions which essentially selected the color and treated it on a separate "layer" by desaturating. This, of course, greatly ameliorated the effect but didn't address the cause. Certain cameras such as the Sony F828 were absolutely "guaranteed" to produce it strongly with any high contrast areas such as a bright gray sky behind green leaves on a tree. This issue seems to have been nearly eliminated in more current systems, or at least greatly reduced. There were endless debates on the "cause" but this chromatic aberration was definitely exacerbated with certain lenses. Someone did a very thorough explanation, but I've forgotten which forum - I think in the Canon forum which would now be more difficult to find because of the various sub-divisions for different dSLR's which didn't exist then.

At any rate, you can greatly improve the "appearance" by selecting for the "color' and desaturating.

Ultimately, CA is a lens quality issue. Normally CA is most visible at wide apertures, and in most cases it dissapears when you stop down. The better the lens, the less CA you will see at wide apertures. Most modern Aspherical lenses have very low levels of CA, even wide open, because the whole point of an Aspherical element is to allow all colours to focus to the same point...Its much harder to this with older spherical lenses unless you add lots of additional elements, increasing lens complexity and price...Most modern lenses contain at least one Asperical element and its why their performance is often better than older spherical equivalents and why older lenses usually show more CA wide open.

The Sigma 8-16mm ultra wide zoom has three Aspherical elements as well as four "FLD" low dispersion glass elements...A very exotic formula indeed, but it brings dividends because its optical performance is undoughtably first rate. Given its extraordinarily wide focal length the maximum CA for the said lens is only 1 pixel wide!...Hardly noticable even when pixel-peeping at 100%.

--
learntomakeslidshows.net

 

[DaSonyGuy]

Well there was one point in the church when the old official photographer threated to leave if I kept taking pictures...I told him "dont let me stop you, theres the door", but then I thought, heck, its my freinds wedding and I dont want to spoil it so I went and sat down...I won out in the end though.

No, you did not win out anything.

What you did was immoral and it is illegal

Not immoral or illegal....I was'nt being paid, so I was'nt a professional on the day...A real professional would'nt have said anything to me as they would be used to others taking photos around them. And there is no law that says only the person paid to photopgraph a wedding can take pictures of it...At least there is'nt here in the UK.

You were completely out of line.

Not at all...I was a guest and had every right to take as many photos as I liked.

First, you interfeared with the paid professionals ability to get photos by being in the way. Even if you were not standing in his way, you distracted him and your friend and his wife and the guests to the point that the photographer had to ask you to cease and desist.

I was'nt in his way, or getting in his way...As a professional he should have just ignored me. It was actually his wife who said something first, then then you can never expect a woman to stay silent for long.

Moreover, the relationship between the photographer and his clients, especially at a wedding, is absolutely critical.

They had no relationship...It was strictly a business transaction and one they did'nt fullfill to the letter either. They got £1800 for a few hours work and nothing more...They did'nt even stay for the reception!...If I had'nt had my camera with me they would'nt have had any shots of the reception do at all.

The bride is always tense and afraid of how she will look in photos and if you are messing with the chemistry betweeen the photographer and his clients you have crossed a line that no professional would cross.

I was'nt a professional on that day. I was just a guest with a camera.

If you were a professional photographer you would never behave that way.

If I was the professional on that day I would'nt have been so insecure with my photography skills and or equipment as to feel worried that their photos might end up better than mine...They were getting paid very good money dont forget, so they should have ignored distractions like me and just got on with earning their easy gotten wages. They did'nt even earn the exorbitant fee they charged as they could'nt be bothered to finish the job they were paid to do.

You were in the way to such an extent that the photographer demanded that you stop. That means the groom and his bride were aware of the conflict and quite literally, you traded on your relationship with your friend to mess with whatever chemistry the photographer had established with the couple.

Again, I was'nt in their way. And they did'nt shout and make a scene if thats what you mean...It was a matter of exchanged wispers.

Once the conflict with the photographer had happened in full view of your friend and his bride, the photographer cannot recapture the chemistry with the couple.

Well, that was there own fault was'nt it. If I was being paid good money to shoot a wedding, I'd just ignore distractions and get on with it, because as a professional that is what iwould be expected of me.

You F_ d it up and it cannot be repaired. Of course the couple will take your side because you are a friend.

Actually, they F_ d up, not me. They were'nt even professional enough to finish the job.

Wedding photography is not about this pose or that background, it is about the relationship that the photographer has established with the couple and you inserted your self into that relationship and destroyed the most important element of his work. How well he is able to interact with the couple.
Second, you took business away from him by selling your photos to your friend.

That just the nature of capitalism...You should know that coming from America!

Besides...If their photos had been any good my freind would have happily bought their photos as well but to be honest...They were rubbish...And I did'nt need to tell my freind they were rubbish as he had perfectly good eyesight and could see for himself.

Whether you like the equipment selection of the paid professional or not or even whether you liked the photos or not it was theft.. I am certain that you influenced your friend to like your photos more as well.

The only theives there were the two so called pofessionals, who ripped my mate off and then did'nt even finish the job they were paid a great deal of money to do.

By the way i have invited many forum members, from another two forums, to shoot with me and so far, 6 forum members have shot with me. The important element there is to shoot with the primary photographer in a way that you enhance each others photos. The object, after all, is to get a good set of photos for the couple. By the way, i always insist that all photos be put into the primary package that the couple gets and they never know which photographer took what shot. It is not a contest, it is an attempt to cover an important event in their lives and you messed with that event and should not have.

Well perhaps things are very different on your side of the pond...Perhaps you just have much bigger weddings to cover than here, but here, its normally one pro working alone.

You could have worked with the photographer but instead you chose to compete with him.

Hey, he started on me first whilst I was happily minding my own business...If he had been a real pro he would have ignored me and got on with his.

 

[Walter S Matthews]

Absolutely remarikable reply.

Mommy, he started it when he hit you back.

He obviously didn't ask anyoe else to stop. You were the one who was causing the problem. He was being paid, as you say, an exorbitent price, to take photos.

Not you.

The fact that he felt it necessary to ask you to stop proves that you were in the way. Whether he noticed or his wife noticed or the alter boy walking by noticed it. It is not relevant who noticed it.

I won't debate it in the future. You were out of line and you should at least consider that if you had not been there doing what you did, his photos would have been better. Once you, as a close friend of the groom, have conflicted with him, he is dead meat so to speak. Whether he had rapport with them before the shoot is not relevant, that can be, and usually is, built during a wedding.

You obviously think you are a better photographer than he is and you are apparently anxious to show your friend et. al. that you are.

You do not understand the meaning of professional courtesy. At a minimunm it was rude and in my book it was outrageous behavior.

 

[Geoff_R]

You do not understand the meaning of professional courtesy. At a minimunm it was rude and in my book it was outrageous behavior.

Agreed....Alf is the type of guy who turns up with his camera thinks he has a point to prove, look at the kit he took, and rather than as he claims taking a few snaps at a friends wedding proceeds to machine gun it while the pro is working, £120 worth of 7x5's from Jessops gets you a lot of prints....and then trys to justify his behaviour by claiming his pics were better than the pros......
best

--
Geoff_R

'Always look on the bright side of life...'
http://www.fightwireimages.com

 

[Walter S Matthews]

dpi is irrelevant for screen displays. dpi is an instruction to the printer driver software.

If you like I will post the images in question.

Frist, the image after Photoshop turns the whole thing into a JPG with full JPG quality is 7264x5440 pixels, it is a 30.27x22.67 @ 240 DPI and the JPG is 23.1 MB.

Second in photoshopin Image Size insert 100 rather than 240 and you get a new image. It is 3027x2267 pixels, it is a 30.27x22.67 @ 100 DPI and it is 4.5 MB jpg

Next reduce the first full resolution image to a 10.68 X 8 at 240 DPI it makes a 2564x1920 pixel image that is a 3.2 MB jpg

Take the second image where 100 DPI was plugged in and reduce the size to 10.68 x 8 at 100 DPI and you get 1068 x 800 pixels image that is a .644 MP jpg

Next take the image that was made by reducing the size to 10.8 x 8 at 240 DPI and drop the DPI to 100 and you get an image that is 1068 x 800 pixels and is a .644 MP jpg.

Finally take the original image and in Image Size in photoshop reduce it to a 10.8x8 @ 100 dpi all in one step. That also nets you a 1068x800 pixel image but the JPG is only .638mp and it looks different than either from above and to my eye worse than either of the two above.

The three images that came from the large image by three different routs do not look the same. I am sure it has to do with how the individual JPG's interact with the data but I am not sure what is better yet. I will see what happens when I reduce a tiff file the same way but I have not done that yet.

For the record, when you reduce the DPI in Image Size in JPG you drop data out of the image and it will show up on a monitor, in print and if you try to do anything with that image. Again, if you want to see examples let me know.

 

[leonard callow]

dpi is irrelevant for screen displays. dpi is an instruction to the printer driver software.

For the record, when you reduce the DPI in Image Size in JPG you drop data out of the image and it will show up on a monitor, in print and if you try to do anything with that image. Again, if you want to see examples let me know.

Walter this is not true. dpi is irrelevant to screen display.period.

try this change dpi to 1,000,000 - the image on screen does not change.
now change dpi to 1 - again the image on screen does not change.period.

if you are reducing for web just decide what size you want the image to be say 900 pixels tall and reduce it once to that size and just ignore the dpi.
one reduction is likely going to be better than two.

--
Leonard

 

[DaSonyGuy]

You do not understand the meaning of professional courtesy. At a minimunm it was rude and in my book it was outrageous behavior.

Agreed....Alf is the type of guy who turns up with his camera thinks he has a point to prove, look at the kit he took.

???...Some cheap old lenses and a slow, low resolution DSLR...Who was going to be impressed by that?...The pros?

and rather than as he claims taking a few snaps at a friends wedding proceeds to machine gun it while the pro is working, £120 worth of 7x5's from Jessops gets you a lot of prints....and then trys to justify his behaviour by claiming his pics were better than the pros......

Now whoa there just a minute Geoff...Firstly, you should know full well that you cant do machine gun photography with an SD14...I was picking my shots very carefully and methodically. I probably only shot 1 to every 100 taken by the pros.

And secondly, I did'nt need to claim my pics were better than the pros, because my friend and his wife could easily see that for themselves because it so was very obvious. I was'nt out to make money but when they both virtually begged me for prints of my pics, it was only fair that I covered my costs...£120 for 50 or so prints is absolute peanuts in comparison to the pros fee of £3600 all in (wedding and prints in a finished wedding album).

I was the "professional photographer" at my sisters wedding. I did'nt charge a penny for my services and even gave her the prints for nothing afterwards as a wedding present...I did'nt make a penny, but it did'nt bother me one bit.

I've been asked to do another wedding but I politely declined, firstly because I have no idea what a fair rate to charge would be and secondly because they are freinds too and charging them a fee I consider too much would leave a bad taste in my mouth...I dont like to see people being ripped off, especially when their friends of mine.

 

[Laurence Matson]

Walter,

You are terribly confused.

First of all, if you do all that you are doing in the form of jpegs, it is no wonder you are ending up with a variety of messes. Saving a file as jpegs repeatedly degrades the image at each step no matter with your settings are. End of story.

Working with tiffs, however, you can change all kinds of things and you will see little degrading. But both of the above are really beside the point.

Your confusion has to do with resizing an image. When doing so you only change the amount of information when you reduce the pixel count along one axis or both axes. For example, an SD1image at 4800x3200 pixels has exactly that many pixels along the respective axes regardless of the dpi or ppi setting. The only thing that changes is the physical print size.

A 4800x3200 pixel image

at 72 ppi is 66.67 x 44.44 inches
at 96 ppi is 50 x 33.33 inches (one common screen resolution)
at 180 ppi is 26.67 x 17.78 inches
at 360 ppi is 13.33 x 8.89 inches

You can do this exercise yourself. In photoshop, open Image Size (alt+command+I) and change the Resolution setting in the Document Size box after unchecking the Resample Image box. You will see that the Pixel Dimensions at the top never change; only the Width and Height change.

If you do the same changes in ppi and leave the Resample Image box (and the Scale Styles and Constrain Proportions boxes) checked, you will see that the pixel count along each axis changes concomitantly.

I hope this makes some sense to you.

dpi is irrelevant for screen displays. dpi is an instruction to the printer driver software.

If you like I will post the images in question.

Frist, the image after Photoshop turns the whole thing into a JPG with full JPG quality is 7264x5440 pixels, it is a 30.27x22.67 @ 240 DPI and the JPG is 23.1 MB.

Second in photoshopin Image Size insert 100 rather than 240 and you get a new image. It is 3027x2267 pixels, it is a 30.27x22.67 @ 100 DPI and it is 4.5 MB jpg

Next reduce the first full resolution image to a 10.68 X 8 at 240 DPI it makes a 2564x1920 pixel image that is a 3.2 MB jpg

Take the second image where 100 DPI was plugged in and reduce the size to 10.68 x 8 at 100 DPI and you get 1068 x 800 pixels image that is a .644 MP jpg

Next take the image that was made by reducing the size to 10.8 x 8 at 240 DPI and drop the DPI to 100 and you get an image that is 1068 x 800 pixels and is a .644 MP jpg.

Finally take the original image and in Image Size in photoshop reduce it to a 10.8x8 @ 100 dpi all in one step. That also nets you a 1068x800 pixel image but the JPG is only .638mp and it looks different than either from above and to my eye worse than either of the two above.

The three images that came from the large image by three different routs do not look the same. I am sure it has to do with how the individual JPG's interact with the data but I am not sure what is better yet. I will see what happens when I reduce a tiff file the same way but I have not done that yet.

For the record, when you reduce the DPI in Image Size in JPG you drop data out of the image and it will show up on a monitor, in print and if you try to do anything with that image. Again, if you want to see examples let me know.

--
Laurence
laurence at appledore-farm dot com

La chance ne sourit qu'aux esprits bien préparés.
Chance favors the prepared mind.
Louis Pasteur

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