Alpha 7 verses E-M1 or something else?

[DT200]

For those not familiar with the E-M1 or the Alpha 7:

• E-M1: Micro 4/3 sensor. Largest electronic VF viewed image of any camera. I would buy it with the 12-40mm, constant F2.8 aperture, Pro lens. (camera + lens about $2398 but includes a small attachable flash)
• Alpha 7: Full frame sensor! I think the viewed image in the EVF is a bit smaller than the image in the E-M1 because the magnification of the VF image in the Alpha 7 is less than in the E-M1. I would buy it with the kit lens, 28-70mm, F3.5-F5.6 OSS lens. (camera + lens about $1998. Does not include small attachable flash.)

... 1. What I'm not sure of is the light capturing ability of a "micro 4/3 sensor with constant F2.8 aperture lens" verses a "full frame sensor with a F3.5-F5.6 aperture lens". Can you help me out with this?

By the image below it is pretty clear that the A7 sensor is better than the tiny one in the E-M1. It just bests it in all measurements.

Newbies often look at the "overall" DxO scores but don't know how to look at the actual measurements for various ISOs. The overall score is pretty arbitrary and means nothing if you are talking about shoot at ISOs 200-6400. Since the EM1 native lenses give you a 1+ stop advantage (and IS with the primes), DxO measurements show the EM1 will be superior for DR and almost identical for noise (with primes and IS the EM1 pulls far ahead).

Lenses have nothing to do with dynamic range and noise. Dynamic range is a function of sensor noise and well capacity and is independent of lenses.

Really? So if you put a F/1.8 lens on a camera and take a picture at night with no flash at 1/60th shutter speed, the DR will be the same as with an F/5.6 lens? Are you starting to understand?

The DR of a camera is independent of the lens you put on it. Period. You can fashion all kind of ideas that bring out this DR or that DR, but in the end, DR is purely a function of well capacity and read noise.

LOL, so images taken at ISO100 and ISO6400 will have the same DR? PLEASE, PLEASE go to DxO's site and read what they have to say.

 

[YRUNVS]

Checking SLRGear I see the the 25mm F/1.4 is sharper wide open according to their blur index. This makes sense since the A7/R have issues with corner sharpness and vignetting. Both are superb lenses and in real life you are not going to see anything noticeably different (except maybe that vignetting).

SLR gear doesn't normalize for format and sensor correct? In another thread Ontario gone used this to suggest that the 25 1.4 out resolved the Canon 6D and 50 1.8. Looking at the actual resolution numbers it was clear that the 50/6D combo out resolved (significantly) the 25 1.4 (on 16mp m4/3) at every common aperture.

I'd say SLR gear's methodology makes sense as you wouldn't want the benchmark for every lens/sensor combo to be a phase one iq180 back and a high quality lens. But comparing SLR gear across formats without considering the relative differences is like comparing the resolution numbers from an OTUS 55 1.4 on a D40 and 50 1.8D on a D800E and concluding the 50D is a better lens.

 

[socode]

So now you don't know what F/1.8 and F/5.6 mean? Most would say I did specify aperture.

Even above I specifically mentioned lenses that had a 1 stop difference in aperture.

1.8 to 5.6 is 3 1/3 stops.

 

[socode]

Really? So if you put a F/1.8 lens on a camera and take a picture at night with no flash at 1/60th shutter speed, the DR will be the same as with an F/5.6 lens?

I think you are confused, since it will be the same if both lenses were set to the same aperture (you didn't specify).

So now you don't know what F/1.8 and F/5.6 mean? Most would say I did specify aperture.

Fantastic, you've read one sentence. Can you read the next one?

And if you wanted the same exposure for different apertures, you should have adjusted the shutter speed accordingly. It's night, so you are are shooting on a tripod? Or indoors?

 

[skyglider]

Hi folks,

Very good discussion in this thread which has been enlightening. Thanks to all for participating.

First, I would like to respond to Dennis who asked:

I'm always curious when people compare the EM1 to the A7 as to why those two cameras ? If a 4/3 sensor is good enough, then why not compare to any of the other APS-C mirrorless bodies around ? Why jump to FF ?

Don't know about others but the two reasons I compared the E-M1 to the Alpha 7 are because:

1. the body of the A7 is unbelievably small for a full frame sensor camera. The A7's body is about the same size as the E-M1. I know the catch is that the lenses for the full frame A7 will be bigger than equivalent lenses for the micro 4/3rds E-M1 but I might be able to live with that. I'll have to check the size and weight of the full frame lens that I am interested in to decide.
2. The A7 has "electronic" first curtain shutter which prevents shutter shock from causing blur in images. The E-M1 doesn't have "electronic" first curtain shutter capability. This is a biggie as I don't want blurred images caused by shutter shock. I'm not sure if the E-M1's first curtain shutter delay after the shutter closes (prior to opening) really prevents blur from shutter shock since there will be some shutter shock when the first curtain shutter opens at slower shutter speeds below 1/200 second. I think I understand why first curtain shutter shock does not affect higher shutter speeds in the E-M1.

I haven't compared the E-M1 to typical "fat" bodied mirrorless cameras with EVFs since a smaller form factor is more appealing for my planned usage.

Follow ups to the questions I asked in my original post are inserted below:

... 1. What I'm not sure of is the light capturing ability of a "micro 4/3 sensor with constant F2.8 aperture lens" verses a "full frame sensor with a F3.5-F5.6 aperture lens". Can you help me out with this?

I think I need to ask this question in another way which is: Disregard the lens used. If the same type of sensor was used in both cameras, how many stops difference does a full frame sensor have over a micro 4/3 sensor?

... 2. How good is the image from the Alpha 7 using it's 4x digital zoom? It's 28-70mm kit lens has only 2.5x zoom so I would need to use the additional 4x digital zoom for more reach. I don't like to change lenses so need the additional 4x digital zoom. (I only want input from Alpha 7 owners who use the 4x digital zoom. I don't want to dilute this thread with why digital zoom is not good from non Alpha 7 owners. Thanks.)

Drj3 addressed this question so thanks. Good points that got me thinking.

... 3. Any other suggestions for an APS-C camera that has a large electronic viewfinder and electronic first curtain shutter that can compare to the Alpha 7 with kit lens?

Shadowhumper suggested the Sony A65. I researched it and found that yes, it is an APS-C camera with a large EVF. But the body is the fat style that I'm not looking for. It's not like the skinny E-M1 or skinny Alpha 7. Thanks for the suggestion though.

Thanks all for participating in this thread. I've read every post and am still digesting all of the info. If only the E-M1 did not have shutter shock problems, it would be a no-brainer as I like it's size, large screen, large EVF, extreme custom-ability of the controls and the 12-40mm F2.8 Pro lens.

Sky

 

[Martin.au]

E-M1 has an electronic first curtain shutter too. It's used when you use "short shutter lag" or whatever option it is in the menu.

 

[OceanFroggie]

I know this sounds nuts, but despite the excellent specs, performance and functionality of these two cameras, I am less than enthused by their appearance. Not the most attractive pieces of consumer hardware. Personally in addition to function, the physical appearance and feel of hardware is a considerable purchasing influence on me (eg camera, phones, laptop, car, TV, etc). Some camera bodies are less than wow looking. Just another angle. IQ and specs alone are not the 'high priestess'.

 

[skyglider]

E-M1 has an electronic first curtain shutter too. It's used when you use "short shutter lag" or whatever option it is in the menu.

Hi Martin,

The E-M1's manual says:

"EM1 anti shock
Choose the delay between the shutter button being
pressed and the shutter being released. This diminishes
camera shake caused by vibrations. This feature is
useful in situations such as microscope photography and
astrophotography. It is also useful for sequential shooting
(P. 55) and self timer photography (P. 55)."

So it appears to me that what happens is when the E-M1's shutter button is pressed, the first curtain shutter closes. Then there's a delay to allow the vibrations from the shutter closing, to dissipate. After the short delay, the first curtain shutter opens to expose the sensor. But there is nothing to prevent vibrations from happening that are caused by the first curtain shutter "opening". Not quite an "electronic" first curtain shutter.

Thanks,
Sky

 

[Martin.au]

E-M1 has an electronic first curtain shutter too. It's used when you use "short shutter lag" or whatever option it is in the menu.

Hi Martin,

The E-M1's manual says:

"EM1 anti shock
Choose the delay between the shutter button being
pressed and the shutter being released. This diminishes
camera shake caused by vibrations. This feature is
useful in situations such as microscope photography and
astrophotography. It is also useful for sequential shooting
(P. 55) and self timer photography (P. 55)."

So it appears to me that what happens is when the E-M1's shutter button is pressed, the first curtain shutter closes. Then there's a delay to allow the vibrations from the shutter closing, to dissipate. After the short delay, the first curtain shutter opens to expose the sensor. But there is nothing to prevent vibrations from happening that are caused by the first curtain shutter "opening". Not quite an "electronic" first curtain shutter.

Thanks,
Sky

Different thing.

The EFCS is the "release lag time" setting.

 

[57LowRider]

X-T1, at least you could go to bed with it. See http://tech.firstpost.com/news-analysis/upcoming-fujifilm-x-t1-images-leaked-launch-216809.html

 

[skyglider]

E-M1 has an electronic first curtain shutter too. It's used when you use "short shutter lag" or whatever option it is in the menu.

Hi Martin,

The E-M1's manual says:

"EM1 anti shock
Choose the delay between the shutter button being
pressed and the shutter being released. This diminishes
camera shake caused by vibrations. This feature is
useful in situations such as microscope photography and
astrophotography. It is also useful for sequential shooting
(P. 55) and self timer photography (P. 55)."

So it appears to me that what happens is when the E-M1's shutter button is pressed, the first curtain shutter closes. Then there's a delay to allow the vibrations from the shutter closing, to dissipate. After the short delay, the first curtain shutter opens to expose the sensor. But there is nothing to prevent vibrations from happening that are caused by the first curtain shutter "opening". Not quite an "electronic" first curtain shutter.

Thanks,
Sky

Different thing.

The EFCS is the "release lag time" setting.

My understanding of the electronic first curtain shutter is that it is purely electronic with no mechanical first curtain shutter. Here's a link that explains how the EFCS works:

http://www.krebsmicro.com/Canon_EFSC/

There is a mechanical second curtain shutter but it is of no consequence since the image capture is already completed when any vibrations from the second curtain shutter occurs.

Sky

 

[Martin.au]

E-M1 has an electronic first curtain shutter too. It's used when you use "short shutter lag" or whatever option it is in the menu.

Hi Martin,

The E-M1's manual says:

"EM1 anti shock
Choose the delay between the shutter button being
pressed and the shutter being released. This diminishes
camera shake caused by vibrations. This feature is
useful in situations such as microscope photography and
astrophotography. It is also useful for sequential shooting
(P. 55) and self timer photography (P. 55)."

So it appears to me that what happens is when the E-M1's shutter button is pressed, the first curtain shutter closes. Then there's a delay to allow the vibrations from the shutter closing, to dissipate. After the short delay, the first curtain shutter opens to expose the sensor. But there is nothing to prevent vibrations from happening that are caused by the first curtain shutter "opening". Not quite an "electronic" first curtain shutter.

Thanks,
Sky

Different thing.

The EFCS is the "release lag time" setting.

My understanding of the electronic first curtain shutter is that it is purely electronic with no mechanical first curtain shutter. Here's a link that explains how the EFCS works:

http://www.krebsmicro.com/Canon_EFSC/

There is a mechanical second curtain shutter but it is of no consequence since the image capture is already completed when any vibrations from the second curtain shutter occurs.

Sky

Yep. Which is how the E-M1 works.

Loading…

www.dpreview.com

 

[drj3]

1. The A7 has "electronic" first curtain shutter which prevents shutter shock from causing blur in images. The E-M1 doesn't have "electronic" first curtain shutter capability. This is a biggie as I don't want blurred images caused by shutter shock. I'm not sure if the E-M1's first curtain shutter delay after the shutter closes (prior to opening) really prevents blur from shutter shock since there will be some shutter shock when the first curtain shutter opens at slower shutter speeds below 1/200 second. I think I understand why first curtain shutter shock does not affect higher shutter speeds in the E-M1.

Either camera should provide excellent results. If you are unsure about a characteristic of the E-M1, then you should probably get the Sony. However, you should know that a poll on the Micro Four Thirds Talk shows that a majority of users have never experienced shutter shock on either the E-M1 or the E-M5. None of the users who have reported shutter shock have done any controlled tests to confirm it (controlling both aperture & ISO). Some of the users who reported shutter shock say that it occurs on a tripod, others say it doesn't, some say with only certain lenses at a narrow range of shutter speeds, others say on all lenses at a wide range of speeds, some say the shutter lag time or delay remove it, others say these have no effect, some say that it only causes vertical blur, others say blur in all directions. There is no consistency in the reports. The majority of users probably believe the ones who report shutter shock simply don't hold the camera securely or move the camera (a potential problem with light weight camera) as they press the shutter.

I did a controlled test with the 12-60mm lens at 40mm on the E-M1, controlling for both aperture and ISO, varying only shutter speed. Auto IBIS was on I used no settings to try to reduce shutter shock. I found no shutter shock effect at any shutter speed. The target was displayed on my 27 inch Samsung PLS monitor, the monitor illumination was varied to produce the same aperture and ISO for all images. All the images looked identical when viewed at 100% and above. Below is an example the center section of the image at 100%, 1/2 the image is at 1/125, the other half is at 1/500. One of the images was flipped in CS6 so that they could easily be compared. If you look at the lighter areas, you can see the pixels and the gaps between the pixels on my 2560x1440 monitor and when you compare them, there are simply are no differences (the raw files before the tif and jpeg conversions are much clearer). The camera was hand held. If there was any shutter shock it did not effect resolution or clarity of the pixel gap images from my monitor, so I do not see how it could ever has a visible effect on any photograph. I cannot say that different lenses would not produce some visible shutter shock, but given the conflicting examples of shutter shock reported by different users, I tend to believe the majority of users are correct and that shutter shock is of little concern. See the attached image.




One half the image at 1/125 the other half at 1/500 - 100% crop



--
drj3

 

[skyglider]

I did a controlled test with the 12-60mm lens at 40mm on the E-M1, controlling for both aperture and ISO, varying only shutter speed. Auto IBIS was on I used no settings to try to reduce shutter shock. I found no shutter shock effect at any shutter speed. The target was displayed on my 27 inch Samsung PLS monitor, the monitor illumination was varied to produce the same aperture and ISO for all images. All the images looked identical when viewed at 100% and above. Below is an example the center section of the image at 100%, 1/2 the image is at 1/125, the other half is at 1/500. One of the images was flipped in CS6 so that they could easily be compared. If you look at the lighter areas, you can see the pixels and the gaps between the pixels on my 2560x1440 monitor and when you compare them, there are simply are no differences (the raw files before the tif and jpeg conversions are much clearer). The camera was hand held. If there was any shutter shock it did not effect resolution or clarity of the pixel gap images from my monitor, so I do not see how it could ever has a visible effect on any photograph. I cannot say that different lenses would not produce some visible shutter shock, but given the conflicting examples of shutter shock reported by different users, I tend to believe the majority of users are correct and that shutter shock is of little concern. See the attached image.


One half the image at 1/125 the other half at 1/500 - 100% crop

Hi Drj3,

Thanks for your detailed info. When I look at the image you posted, I do see a shadow type blur above and below each vertical bar. There is also some shadow blur on the sides of some bars but not others. Could it be that the shadow blur on the tops and bottoms of the vertical bars are caused by shutter shock?

Thanks,
Sky

 

[Martin.au]

So you don't actually know what shutter shock is, nor the effects?

Those "shadows" are part of the image. You can't have blurring of that magnitude and still keep the pixel detail. You also can't have shadows like that occurring in some parts of the image, but not others if it was due to shutter shock.

 

[skyglider]

So you don't actually know what shutter shock is, nor the effects?

Those "shadows" are part of the image. You can't have blurring of that magnitude and still keep the pixel detail. You also can't have shadows like that occurring in some parts of the image, but not others if it was due to shutter shock.

Thank you,
Sky

 

[drj3]

I did a controlled test with the 12-60mm lens at 40mm on the E-M1, controlling for both aperture and ISO, varying only shutter speed. Auto IBIS was on I used no settings to try to reduce shutter shock. I found no shutter shock effect at any shutter speed. The target was displayed on my 27 inch Samsung PLS monitor, the monitor illumination was varied to produce the same aperture and ISO for all images. All the images looked identical when viewed at 100% and above. Below is an example the center section of the image at 100%, 1/2 the image is at 1/125, the other half is at 1/500. One of the images was flipped in CS6 so that they could easily be compared. If you look at the lighter areas, you can see the pixels and the gaps between the pixels on my 2560x1440 monitor and when you compare them, there are simply are no differences (the raw files before the tif and jpeg conversions are much clearer). The camera was hand held. If there was any shutter shock it did not effect resolution or clarity of the pixel gap images from my monitor, so I do not see how it could ever has a visible effect on any photograph. I cannot say that different lenses would not produce some visible shutter shock, but given the conflicting examples of shutter shock reported by different users, I tend to believe the majority of users are correct and that shutter shock is of little concern. See the attached image.


One half the image at 1/125 the other half at 1/500 - 100% crop

Hi Drj3,

Thanks for your detailed info. When I look at the image you posted, I do see a shadow type blur above and below each vertical bar. There is also some shadow blur on the sides of some bars but not others. Could it be that the shadow blur on the tops and bottoms of the vertical bars are caused by shutter shock?

Thanks,
Sky

No, one half is at 1/500 the other half at 1/125 and the faster speed would be above anything anyone has indicted should produce shutter shock. It really made no difference, I could posted the 1/640 or any other faster shutter speed or the 1/40 second image. The only way I could distinguish between the images at different shutter speeds was by the EXIF information. The image I found on the net was not that good, so the horizontal bars at 100% simply looked that way when loaded into CS6 which was what I used for the test pattern. The light areas which show the pixel gaps are from the monitor and have no blur and I cannot image even photographing anything where I would worry about even finer detail. These did look much better before the conversion to tif (Olympus Viewer) and the conversion to jpeg (CS6) and then the upload to the gallery.

--
drj3

 

[skyglider]

I did a controlled test with the 12-60mm lens at 40mm on the E-M1, controlling for both aperture and ISO, varying only shutter speed. Auto IBIS was on I used no settings to try to reduce shutter shock. I found no shutter shock effect at any shutter speed. The target was displayed on my 27 inch Samsung PLS monitor, the monitor illumination was varied to produce the same aperture and ISO for all images. All the images looked identical when viewed at 100% and above. Below is an example the center section of the image at 100%, 1/2 the image is at 1/125, the other half is at 1/500. One of the images was flipped in CS6 so that they could easily be compared. If you look at the lighter areas, you can see the pixels and the gaps between the pixels on my 2560x1440 monitor and when you compare them, there are simply are no differences (the raw files before the tif and jpeg conversions are much clearer). The camera was hand held. If there was any shutter shock it did not effect resolution or clarity of the pixel gap images from my monitor, so I do not see how it could ever has a visible effect on any photograph. I cannot say that different lenses would not produce some visible shutter shock, but given the conflicting examples of shutter shock reported by different users, I tend to believe the majority of users are correct and that shutter shock is of little concern. See the attached image.


One half the image at 1/125 the other half at 1/500 - 100% crop

Hi Drj3,

Thanks for your detailed info. When I look at the image you posted, I do see a shadow type blur above and below each vertical bar. There is also some shadow blur on the sides of some bars but not others. Could it be that the shadow blur on the tops and bottoms of the vertical bars are caused by shutter shock?

Thanks,
Sky

No, one half is at 1/500 the other half at 1/125 and the faster speed would be above anything anyone has indicted should produce shutter shock. It really made no difference, I could posted the 1/640 or any other faster shutter speed or the 1/40 second image. The only way I could distinguish between the images at different shutter speeds was by the EXIF information. The image I found on the net was not that good, so the horizontal bars at 100% simply looked that way when loaded into CS6 which was what I used for the test pattern. The light areas which show the pixel gaps are from the monitor and have no blur and I cannot image even photographing anything where I would worry about even finer detail. These did look much better before the conversion to tif (Olympus Viewer) and the conversion to jpeg (CS6) and then the upload to the gallery.

--
drj3

Hi drj3,

I appreciate the time you took to post your info and your follow up post.

Best regards,
Sky

 

[stevo23]

For those not familiar with the E-M1 or the Alpha 7:

• E-M1: Micro 4/3 sensor. Largest electronic VF viewed image of any camera. I would buy it with the 12-40mm, constant F2.8 aperture, Pro lens. (camera + lens about $2398 but includes a small attachable flash)
• Alpha 7: Full frame sensor! I think the viewed image in the EVF is a bit smaller than the image in the E-M1 because the magnification of the VF image in the Alpha 7 is less than in the E-M1. I would buy it with the kit lens, 28-70mm, F3.5-F5.6 OSS lens. (camera + lens about $1998. Does not include small attachable flash.)

... 1. What I'm not sure of is the light capturing ability of a "micro 4/3 sensor with constant F2.8 aperture lens" verses a "full frame sensor with a F3.5-F5.6 aperture lens". Can you help me out with this?

By the image below it is pretty clear that the A7 sensor is better than the tiny one in the E-M1. It just bests it in all measurements.

Newbies often look at the "overall" DxO scores but don't know how to look at the actual measurements for various ISOs. The overall score is pretty arbitrary and means nothing if you are talking about shoot at ISOs 200-6400. Since the EM1 native lenses give you a 1+ stop advantage (and IS with the primes), DxO measurements show the EM1 will be superior for DR and almost identical for noise (with primes and IS the EM1 pulls far ahead).

Lenses have nothing to do with dynamic range and noise. Dynamic range is a function of sensor noise and well capacity and is independent of lenses.

Really? So if you put a F/1.8 lens on a camera and take a picture at night with no flash at 1/60th shutter speed, the DR will be the same as with an F/5.6 lens? Are you starting to understand?

The DR of a camera is independent of the lens you put on it. Period. You can fashion all kind of ideas that bring out this DR or that DR, but in the end, DR is purely a function of well capacity and read noise.

LOL, so images taken at ISO100 and ISO6400 will have the same DR? PLEASE, PLEASE go to DxO's site and read what they have to say.

I never said that ISO doesn't vary with DR. I'll say it again: The DR of a camera is independent of the lens you put on it. ISO is also independent of the lens you put on the camera.

I don't know why you keep putting words in my mouth. Is this a technique of yours?

 

[stevo23]

For those not familiar with the E-M1 or the Alpha 7:

• E-M1: Micro 4/3 sensor. Largest electronic VF viewed image of any camera. I would buy it with the 12-40mm, constant F2.8 aperture, Pro lens. (camera + lens about $2398 but includes a small attachable flash)
• Alpha 7: Full frame sensor! I think the viewed image in the EVF is a bit smaller than the image in the E-M1 because the magnification of the VF image in the Alpha 7 is less than in the E-M1. I would buy it with the kit lens, 28-70mm, F3.5-F5.6 OSS lens. (camera + lens about $1998. Does not include small attachable flash.)

... 1. What I'm not sure of is the light capturing ability of a "micro 4/3 sensor with constant F2.8 aperture lens" verses a "full frame sensor with a F3.5-F5.6 aperture lens". Can you help me out with this?

By the image below it is pretty clear that the A7 sensor is better than the tiny one in the E-M1. It just bests it in all measurements.

Newbies often look at the "overall" DxO scores but don't know how to look at the actual measurements for various ISOs. The overall score is pretty arbitrary and means nothing if you are talking about shoot at ISOs 200-6400. Since the EM1 native lenses give you a 1+ stop advantage (and IS with the primes), DxO measurements show the EM1 will be superior for DR and almost identical for noise (with primes and IS the EM1 pulls far ahead).

I think you're use of the word Newbies and the derogatory nature of your post is quite rude - no matter the subject.