Using extension tubes with long lens

[Interceptor121]

A longer focal length provides more background blur at a given f-stop and magnification. If I need to stop down to f/9 to get a whole dragonfly in focus when it's filling the frame, then I'll need to use f/9 for sufficient DOF regardless of the lens. Due to the greater compression, 400mm 0.25x f/9 will provide more background blur than 200mm 0.25x f/9.

The blur depends only on fstop given the same magnification and I have tested it too

so once the subject size in the frame is the same the depth of field only depends on the aperture

Did you actually read my comment before responding?

I already pointed out that at the same subject framing depth of field only depends on the f-stop. What did you think I meant by "I'll need to use f/9 for sufficient DOF regardless of the lens"?

Depth of field isn't the same thing as background blur. In fact, DOF calculator apps usually provide separate figures for both, e.g. dofsimulator.net

the field of view behind is what is influenced by the focal length the blur isn’t

Of course the focal length you use can influence background blur. With the same framing and depth of field, shooting from further away with a narrower field of view will magnify the background more (i.e. greater lens compression), leading to a more blurred background in your image.

For example, if I shoot a butterfly on a flower with grass in the background, a long lens might smoothly blur the grass to little more than a green texture, while a wide angle lens at the same f-stop might clearly show every blade. There's obviously not such a difference between 200mm and 400mm, but it's still easily noticeable.

Here's a nice example borrowed from a Bob Atkins article:



He also has a background blur calculator on his site.

Do you really not know this, or are you just arguing for the sake of arguing?

You have not read the article you reference yourself?

As you would expect, at the same magnification, the faster the lens, the smaller the depth of field. This also means that the background close to subject will be blurred more by the faster lens. In this case the 50mm lens at f1.4 gives slightly greater blurring for objects up to about 1m behind the subject in focus. However as you go further back, the lens with the largest physical aperture starts to show the most blur, and by the time you're at infinity, the 135mm lens at f2 lens will give almost twice as much blurring (actually 1.9x as much).

When you shoot a bug o a leave you typically have zero space behind so the real life example is closer to case 1 background close and faster lens than the lens having something behind at infinity

This is why for macro subjects that are sitting on something the focal length matters less than aperture if you just wanted to have a little detail only in focus

So for practical reasons shooting close ups with things that are laying or are very close to something aperture is all that matters to blur the background

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[SteveY80]

A longer focal length provides more background blur at a given f-stop and magnification. If I need to stop down to f/9 to get a whole dragonfly in focus when it's filling the frame, then I'll need to use f/9 for sufficient DOF regardless of the lens. Due to the greater compression, 400mm 0.25x f/9 will provide more background blur than 200mm 0.25x f/9.

The blur depends only on fstop given the same magnification and I have tested it too

so once the subject size in the frame is the same the depth of field only depends on the aperture

Did you actually read my comment before responding?

I already pointed out that at the same subject framing depth of field only depends on the f-stop. What did you think I meant by "I'll need to use f/9 for sufficient DOF regardless of the lens"?

Depth of field isn't the same thing as background blur. In fact, DOF calculator apps usually provide separate figures for both, e.g. dofsimulator.net

the field of view behind is what is influenced by the focal length the blur isn’t

Of course the focal length you use can influence background blur. With the same framing and depth of field, shooting from further away with a narrower field of view will magnify the background more (i.e. greater lens compression), leading to a more blurred background in your image.

For example, if I shoot a butterfly on a flower with grass in the background, a long lens might smoothly blur the grass to little more than a green texture, while a wide angle lens at the same f-stop might clearly show every blade. There's obviously not such a difference between 200mm and 400mm, but it's still easily noticeable.

Here's a nice example borrowed from a Bob Atkins article:



He also has a background blur calculator on his site.

Do you really not know this, or are you just arguing for the sake of arguing?

You have not read the article you reference yourself?

As you would expect, at the same magnification, the faster the lens, the smaller the depth of field. This also means that the background close to subject will be blurred more by the faster lens. In this case the 50mm lens at f1.4 gives slightly greater blurring for objects up to about 1m behind the subject in focus. However as you go further back, the lens with the largest physical aperture starts to show the most blur, and by the time you're at infinity, the 135mm lens at f2 lens will give almost twice as much blurring (actually 1.9x as much).

When you shoot a bug o a leave you typically have zero space behind so the real life example is closer to case 1 background close and faster lens than the lens having something behind at infinity

This is why for macro subjects that are sitting on something the focal length matters less than aperture if you just wanted to have a little detail only in focus

Again, I have to ask, what did you you think I meant by "I'll need to use f/9 for sufficient DOF regardless of the lens"?

I'm talking about a scenario where a specific depth of field is needed for the desired shot, and therefore the same f-stop will be used regardless of how fast the lens is.

If you look at Trevor's original post, you'll find that he stopped down for additional DOF in most of his images, e.g. the last 3 are all shot at f/11. Using a faster lens to blur the background would mean blurring more of the subject. If you want deep DOF (and can't stack the shot) then opening the aperture wider simply isn't an option.

So for practical reasons shooting close ups with things that are laying or are very close to something aperture is all that matters to blur the background

It isn't unusual for there to be significant separation between the subject and background when shooting things like flowers and insects. Subjects I shoot close-up at 400mm, like dragonflies and butterflies, often perch on a single flower or stem that's at least somewhat isolated, e.g.:



Again, you could look at Trevor's last few images. The green background foliage is far enough away to be quite well blurred even at f/11, especially in his shot of the large skipper.

Even when there isn't much separation between background and subject the focal length still makes a difference. I've sometimes switched from a faster and wider lens to the 400mm precisely for that reason.

This dragonfly that was in the middle of a mess of grasses and stems. It's shot at f/10, because that's the widest aperture I could use and still get its head sharp. I started out shooting with my 40-150mm f/2.8, but switching to 400mm made the best of a bad background:



This orchid was a short distance from the clutter of foliage behind it, but taking off the faster and wider lens I'd been using, and shooting with the 400mm at f/8, ended up giving me the better background:



This is something I've found out from practical experience using different lenses for a variety of close up subjects.

Here are a couple of quick background clutter worst case scenario test shots I took walking home through some waste ground with my 100-400mm and 45-175mm:


170mm


400mm

The flowerhead is only a couple of inches in front of the mess of grass stems behind it. Even in that extreme situation, with very little separation, the longer focal length still makes a subtle, but noticeable, difference.

 

[bchppp]

I bought a set of 10/16mm extension tubes as a cheap way to shorten the focus distance on my 75-300 with my E-M5 III for trips to botanical gardens. I was looking for a lighter travel kit instead of my using my E-M1 III with PL100-400. Focus at 300mm is limited to less than about 18 feet but the combo works quite well. I bought a second set of tubes for my E-M10 IV/40-150 f/4-5.6 kit; good results there, too. Either of these are now my go to setups for bugs and flowers

All below various combinations of camera and lenses, all with 16mm extension tubes.

Those are stunning and sharp images.

I've never used an extension tube because of the inconvenience of putting it on and off behind a lens. Maybe you leave the setup permanently in order to avoid the hassle?

Or maybe you don't use a double-element close-up filter because it's so heavy? In February I purchased the last unit of Canon 77mm 500D from Samy's. I couldn't believe they actually had a brand new one in stock! However, I had no idea how heavy it is. I hate the weight and I won't use it. I bought it in anticipation of buying Canon's RF 70-200 f/4, but I changed my mind and am now patiently waiting for Nikon Z 105 Macro to be in-stock. If they don't have the Nikon by Feb, I'll go with Panasonic Leica 45mm macro.

 

[gary0319]

I bought a set of 10/16mm extension tubes as a cheap way to shorten the focus distance on my 75-300 with my E-M5 III for trips to botanical gardens. I was looking for a lighter travel kit instead of my using my E-M1 III with PL100-400. Focus at 300mm is limited to less than about 18 feet but the combo works quite well. I bought a second set of tubes for my E-M10 IV/40-150 f/4-5.6 kit; good results there, too. Either of these are now my go to setups for bugs and flowers

All below various combinations of camera and lenses, all with 16mm extension tubes.

Those are stunning and sharp images.

I've never used an extension tube because of the inconvenience of putting it on and off behind a lens. Maybe you leave the setup permanently in order to avoid the hassle?

Or maybe you don't use a double-element close-up filter because it's so heavy? In February I purchased the last unit of Canon 77mm 500D from Samy's. I couldn't believe they actually had a brand new one in stock! However, I had no idea how heavy it is. I hate the weight and I won't use it. I bought it in anticipation of buying Canon's RF 70-200 f/4, but I changed my mind and am now patiently waiting for Nikon Z 105 Macro to be in-stock. If they don't have the Nikon by Feb, I'll go with Panasonic Leica 45mm macro.

Actually, not much of an inconvenience, at all. I pretty much know ahead of time if I’m going to be using the tube and put it on before setting out. Flowers and bugs, the tube goes on. Distant subjects, the tube stays in the bag.

I’ve had some good quality two element close up lenses and they are heavy and not transferable between lenses with different size front elements. For me a $30 set of autofocus extension tubes is the better option.

 

[Matt Ward]

Great work... I really feel this is an aspect that many overlook. I have been using extension on my 5Dii and 7D for years with 300 and 400mm lenses.

The working distance increase often prevents the critters for being alarmed and helps to prevent shadows in the field of view.

 

[Pedagydusz]

I bought a set of 10/16mm extension tubes as a cheap way to shorten the focus distance on my 75-300 with my E-M5 III for trips to botanical gardens. I was looking for a lighter travel kit instead of my using my E-M1 III with PL100-400. Focus at 300mm is limited to less than about 18 feet but the combo works quite well. I bought a second set of tubes for my E-M10 IV/40-150 f/4-5.6 kit; good results there, too. Either of these are now my go to setups for bugs and flowers

All below various combinations of camera and lenses, all with 16mm extension tubes.

Those are stunning and sharp images.

I've never used an extension tube because of the inconvenience of putting it on and off behind a lens. Maybe you leave the setup permanently in order to avoid the hassle?

Or maybe you don't use a double-element close-up filter because it's so heavy? In February I purchased the last unit of Canon 77mm 500D from Samy's. I couldn't believe they actually had a brand new one in stock! However, I had no idea how heavy it is. I hate the weight and I won't use it. I bought it in anticipation of buying Canon's RF 70-200 f/4, but I changed my mind and am now patiently waiting for Nikon Z 105 Macro to be in-stock. If they don't have the Nikon by Feb, I'll go with Panasonic Leica 45mm macro.

As it is clear from other posts in this thread, Extension Tubes and Diopter filters do quite different things when used with long lenses, they are not really an alternative, to be chosen only for price and convenience of use.

ET are less convenient, to be put on and off they require that the main lens is detached and re-attached. With long lenses the magnification provided with ETs is relatively small. It is sometimes a quite important change, in some cases is enough to "make" a picture. They can help decisively making the subject closer to fill a frame, so they can be very useful, but it is not a dramatic magnification.

OTOH, close-up diopter filters have in general a much greater magnification. Not so much the EF 500D, but the 250D makes a difference! And you can even stack them.

However, there is another difference between ETs and Diopter filters: working distance. With ETs, the working distance is a bit smaller that without them (I can't quantify it just now). So with ETs and a long lens, with ETs you can get a bit closer, and get a bit larger images (like in case of the OP). It can make all the difference to photograph butterflies that are just out of reach (shrubs, banks, fences...). You can with ETs get sufficient magnification for the photo to work. And you loose light, of course, but the results can be rewarding. I have even photographed small birds with the 100-400 and ETs.

With Diopter "filters", it is the opposite: working distance is much smaller, so is the working range (for a given FL, maximum and minimum distance no so far apart), nothing remotely close to infinite focussing, but greater magnification. With the right combination, much greater. And no light loss, plus more convenient to get on and off.

And a much greater investment.

 

[Michael Benveniste]

Great work... I really feel this is an aspect that many overlook. I have been using extension on my 5Dii and 7D for years with 300 and 400mm lenses.

The working distance increase often prevents the critters for being alarmed and helps to prevent shadows in the field of view.

Extension tubes don't increase working distance. Perhaps you are thinking of teleconverters?

 

[Matt Ward]

Great work... I really feel this is an aspect that many overlook. I have been using extension on my 5Dii and 7D for years with 300 and 400mm lenses.

The working distance increase often prevents the critters for being alarmed and helps to prevent shadows in the field of view.

Extension tubes don't increase working distance. Perhaps you are thinking of teleconverters?

I stated that poorly...

When compared to using a macro or near macro lens, such as the Canon 100/2,8... it is easier to fill the frame with an extended 300 or 400mm lens. By working distance, I a referencing front of lens to subject compared to a macro lens and still working within the range of AF.

I have used this several times to capture butterflies and smallish animals from a comfortable distance with decent frame fill. Not that you can hit macro ranges with the setup, but it is not often needed.

Couple of images with no exif.. but either shot with extended 300/f4 IS L or 400/F5.6 L. Also, may hand held macro rig, including extension tube...











--
Panasonic G5, Canon 7D, Canon 5D ii & Canon T3i full spectrum

 

[bchppp]

Actually, not much of an inconvenience, at all. I pretty much know ahead of time if I’m going to be using the tube and put it on before setting out. Flowers and bugs, the tube goes on. Distant subjects, the tube stays in the bag.

I’ve had some good quality two element close up lenses and they are heavy and not transferable between lenses with different size front elements. For me a $30 set of autofocus extension tubes is the better option.

A good strategy since you're doing just one type of shooting per outing. If I were to use it that way, I would prefer ext tubes also. I bought the closeup filter because my original plan was to hike with just one lens (70-200) and extend it's versatility further; in any outing, I was never going shoots only closeups. Now I'll just get a macro lens and use it purely and not add anything to it.

 

[gary0319]

Actually, not much of an inconvenience, at all. I pretty much know ahead of time if I’m going to be using the tube and put it on before setting out. Flowers and bugs, the tube goes on. Distant subjects, the tube stays in the bag.

I’ve had some good quality two element close up lenses and they are heavy and not transferable between lenses with different size front elements. For me a $30 set of autofocus extension tubes is the better option.

A good strategy since you're doing just one type of shooting per outing. If I were to use it that way, I would prefer ext tubes also. I bought the closeup filter because my original plan was to hike with just one lens (70-200) and extend it's versatility further; in any outing, I was never going shoots only closeups. Now I'll just get a macro lens and use it purely and not add anything to it.

I've owned the Oly 60mm Macro, twice. I just could never get sharp close up pics with it hand held. Maybe it's my age which makes getting down close to the ground for low bugs an issue (easier to squat from a distance). or just that I needed to get so close to the bugs that they flew away before the shot.

Anyway both 60's are now in someone else's bag.

 

[bchppp]

All good points and I was pretty much aware of them (but never used them).

OTOH, close-up diopter filters have in general a much greater magnification. Not so much the EF 500D, but the 250D makes a difference! And you can even stack them.

2x (500D) being less magnification, it's sharper though.... Stacking closeup filters? Oh no, not for some people like me. I'm a pixel peeper, which is why I like Gary's sharp images.

With Diopter "filters", it is the opposite: working distance is much smaller, so is the working range (for a given FL, maximum and minimum distance no so far apart), nothing remotely close to infinite focussing, but greater magnification. With the right combination, much greater. And no light loss, plus more convenient to get on and off.

Diopters (closeup filters) do have their place. It's practical when you're going on a longer hike to do multiple types of photography and want to travel light with minimal gear.

--
You know what's the bizarrest thing in life? Life!

 

[bchppp]

I've owned the Oly 60mm Macro, twice. I just could never get sharp close up pics with it hand held. Maybe it's my age which makes getting down close to the ground for low bugs an issue (easier to squat from a distance). or just that I needed to get so close to the bugs that they flew away before the shot.

Anyway both 60's are now in someone else's bag.

Nope, it's not you. We all know Oly has some great lenses. But regarding the Oly 60 macro, I've read a lot of reviews and viewed many images that were suppose to be sharp but weren't. The thing about many lens reviews is that they rate them partly based on how inexpensive a lens is. Which is why I peruse sites that do lab testing AND show the results (visit more than one site). And, at times, the reviewer's words are more glowing than what their chart shows. For example, this one site (that I still like) gave all 3 macro lenses 5 stars, yet their own chart shows they should be approximately 5, 4 and 3.5 stars.

Having said that, I do understand that some people don't mind using a lens that isn't critically sharp.

--
You know what's the bizarrest thing in life? Life!

 

[bchppp]

BTW, is anyone here planning to buy a 77mm close-up filter? The thing is heavy, you know (I'd say about 9 freaking ounces!). If so, I can sell the brand new (opened but unused) Canon 77mm 500D for a $15 shipping charge via PayPal. To someone who will use it and not planning to resell.

I'm not a hoarder and I'll never use it. It was a "special order" item and non-returnable even though it was in-stock. At the time, I was like it's such a hard-to-get item, so why would I want to return it anyway. I don't want to get the most money by putting up for sale through the buy and sell forum. Once I put up one item for sale but it was quickly buried down the line, as that forum is poorly organized.

 

[jalywol]

Sent you a PM.

 

[bchppp]

Even when there isn't much separation between background and subject the focal length still makes a difference. I've sometimes switched from a faster and wider lens to the 400mm precisely for that reason.

This dragonfly that was in the middle of a mess of grasses and stems. It's shot at f/10, because that's the widest aperture I could use and still get its head sharp. I started out shooting with my 40-150mm f/2.8, but switching to 400mm made the best of a bad background:

I'm chiming in. A longer focal length lens, like 200 to 400mm range, are indeed great for subjects you shoot like dragonflies, butterflies, and larger flowers. Uniquely, they combine subject isolation and good depth of field, which is otherwise hard to do without focus stacking. Plus some subjects move too much to do focus stacking. As for me, I'm mostly into tiny uncultivated wildflowers, so I must get close.

 

[bchppp]

Sent you a PM.

Gee, sorry about that, I should have allowed instant PM. It is now enabled and it will be for several days.

Edited to add:

Somehow, I still got your PM before I enabled it (??) and I replied to you. If you got my reply, please answer be back thru PM. Also, how come I can't PM you from my end? (Once I responded to you by clicking the notice, I couldn't see your message nor mine anymore. Weird. Please PM again and see if the system is operating normally)

--
You know what's the bizarrest thing in life? Life!

 

[jalywol]

Sent you a PM back...let me know if you get it.

Oh, and just click "show all messages" if the dialogue box is blank, and it will take you to the full "messages" page.

-J

 

[bchppp]

The Canon 500D closeup filter is SOLD and it's going to a good home. Thank you.

 

[Bobapingu]

I haven't used extension tubes with my Oly 300m f4 PRO but sometimes when out and about looking for birds with just that lens, I'll see something close worth snapping. I'm often amazed at it's macro abilities.




Lambertia formosa

 

[Pedagydusz]

[...]

Diopters (closeup filters) do have their place. It's practical when you're going on a longer hike to do multiple types of photography and want to travel light with minimal gear.

Yes! It is exactly what I usually take to travel light: 500D!