Canon 40D / EF-S 10-22mm Edge Focus Issues

Hey Gang,

new to posting on WP, but not new to the great information on this site.

I primarily shoot WA and converted over from an Olympus 5050 WA setup to a Canon 40D / EF-S 10-22mm about 8 months ago. I went to the 40D to get increased flexibility and improved image quality over what was a well working 5050 setup. However, I've been very frustrated with the WA results that I'm getting and hope you guy's can help me out. Here's what I have going on, and this is the old age topic of "Edge Focus" once again.

My Setup:

Canon 40D, EF-S 10-22mm, Ikelite housing, dual Ike-125 strobes (I'm using an 8" port and the port length is correct).

Results:

1. Edge focus problems throughout 10-22mm range. Edge focus issues are worse at the lower end of the focal range.

2. Close WA work of reefs are fair to good focus in the middle, but the outer edges are very bad, and way out of focus.

What I've tried:

1. +2 B+W Diopter... Slight improvement to the edge focus, but now added Chromatic Aberration and Pin Cushion.

2. +4 B+W Diopter... Same results as above, but more Chromatic Aberration and more Pin Cushion.

3. Tried stopping down lens, but this has also very slight improvement.

Experiments (Compared no diopter with +2 and +4 inside 2 Ft water tank, using square grid to check focus. Shots were done at ~ 2 ft distance):

First off the 40D and 10-22mm pair did not have any issues with close focus.

1. No Diopter shows major edge focus problems throughout range, with slight decreased edge focus issues at 22mm.

2. +2 Diopter shows slight improvement on edge focus throughout range, but now introduces pin cushion and chromatic aberration.

3. +4 Diopter shows about the same improvement on edge focus at #2 above, maybe slightly better. However, now we have two times the pin cushion and chromatic aberration.

Photoshop.

1. Tried to dial out the pin cushion in PS, which works fine.

2. Tried to dial out the Chromatic Aberration in PS, but to do so you now lose some picture color.

From Wetpixel:

1. I'm hearing that the Tokina 10-17mm works better UW with the Canon 40D and the edge focus is better? Is this really true and if so how much better?

2. What are the results with the Tokina 12-24mm? I like the range on this one better.

Gang, I'm really thinking of going back to my 5050, which was a WA setup without the Dome housing (I got ~ 100 degrees coverage on this Inon lens setup). I do understand that introducing the Dome port to the picture is what causes the edge focus issues. Also, having the correct port length is important, which I've done and I've talked to Ikelite and Backscatter, and both recommended the +2 / +4 Diopter. The results from the added diopter changes were not acceptable unless you only care about the middle of a shot?! The 40D and 10-22mm setup works great top side, but I have to say I'm really disappointed UW with it. I love WA UW photography and at this point would hope there is a real solution to my edge focus problems? Does the Tokina 10-17mm really solve the problem? If so, why would this combination work better? It is a smaller lens thus the port size would have to change also...

I would really appreciate some help here!

Cheers

Derek...

http://www.pbase.com/derek_emmett

When the 10-22 first came out, I did a test for Ikelite shooting the 10-22 with the 8" dome and various extensions. I found that when I got the right extension, I was able to get good (not great) results even without a diopter.

Do a search in the Wetpixel library - I think I posted my results.

My guess is that you may think you have the right extension, and the person you talked to at Ikelite may think so too - but you may not. The 10-22 is a great lens.

Of course the Tokina has sharper corners but that's because it's a fisheye lens - and has the accompanying barrel distortion.

Cheers

James

When the 10-22 first came out, I did a test for Ikelite shooting the 10-22 with the 8" dome and various extensions. I found that when I got the right extension, I was able to get good (not great) results even without a diopter.

 

Do a search in the Wetpixel library - I think I posted my results.

 

My guess is that you may think you have the right extension, and the person you talked to at Ikelite may think so too - but you may not. The 10-22 is a great lens.

 

Of course the Tokina has sharper corners but that's because it's a fisheye lens - and has the accompanying barrel distortion.

 

Cheers

James

Hi James,

thank you! I did try looking for your post that you did some Canon 10-22mm port length work on, but could not find it? I tried key words like; edge focus, 10-22mm, port length.. I even tried to include your name, but you have over 8k posts! Is there a better key word that I should be using?

Thanks

Derek...

I think it's an actual review in our library or reviews section.

Cheers

James

I think it's an actual review in our library or reviews section.

 

Cheers

James

here it is....

http://wetpixel.com/i.php/full/canon-10-22...te-8-dome-port/

Hey Guy's,

I did find this link, but there is no mention of the correct port body length. In fact, I was wondering what port body you did use? The pictures with the 8" dome and the crops you have with that are far better than anything I've seen on my personal setup? I will attach some crops later and you will see what I'm talking about. The port body I'm using for my 40D/10-22mm setup up is the Ikelite 5510.22 with the 5510.45 dome assembly. Ikelite swears by this port body for my combination, but I'm telling you the results are poor when the shots are viewed at 100%. I can be 3 + ft away from the subject and get very poor edge performance.

I can't believe there isn't a bigger out cry about the performance here? Or does everyone just accept these perfomance limitations? There has to be a better solution? Does anyone have WA shots with a Canon 40D and the 10-22mm, using the Ikelite housing? I would like to see their WA 100% crop results and compare if they are having the same problem. I have a friend using a Aqatica housing and a Canon 20D with the 10-22mm. His results seem much better also? He does have some edge focus issues, but not to the scale I'm seeing with mine? We don't live close enough for me to measure/compare, etc...

There was a posting on the web (I can't find it anymore), but there was someone that did go through all the port length sizes to find the best edge focus. One of his final quote was, "You get far more edge focus improvement with a +2 diopter than you get with the correct port length". I was sold on that and got a +2 diopter, but those edge focus improvements were only slightly better...

I have a Galapagos trip coming up this November... I want to go with a setup that I know performs very well, as I'm sure you all can understand...

Thanks

Derek...

Hi Derek,

I know this sounds kind of crazy - but can you buy a few different extension ring lengths and test them out in the pool before your galapagos trip? Then send back the ones you don't need? Ikelite is pretty good about stuff like that.

Cheers

James

Hi Derek,

 

I know this sounds kind of crazy - but can you buy a few different extension ring lengths and test them out in the pool before your galapagos trip? Then send back the ones you don't need? Ikelite is pretty good about stuff like that.

 

Cheers

James

Hey James,

not crazy at all! I'm calling Ikelite this week and will see if they can work with me on this issue. It just seems that something is not even remotely right about the dome/extension/lens combination... I'm guessing that a 10" Dome (if available) would be better with the Canon 10-22mm, due to the bigger dome radius. I'm also assuming this is why the Tokina Fisheye 10-17mm allegedly works better with the 8" dome, as the radius of the dome suits it?

Cheers

Derek...

Derek,

After going through a progression of Canon dSLR bodies all in Ikelite housings and using the 8" dome port with both rectilinear lenses (I had a Canon 10-22mm EF-S) I think you are just going to frustrate yourself looking for tack sharp edges with the Canon 10-22mm EF-S lens especially at 10mm.

The testing you're thinking of was done by Jonathan Bird, and he was shooting a Nikon dSLR and Nikon 12-24mm lens. His tests resulted in the mid-length extension Ikelite lists for that lens and the Canon 10-22mm EF-S lens you have.

Lots of shooters here at Wetpixel have added more or less extension, added +2 to +4 diopters as you have and still are not happy at 10mm with that lens.

MY opinion is NO rectilinear lens trying to focus on the curved image a dome port creates underwater will be as sharp as a fisheye lens. Which is why you see so many folks like Alex Mustard, myself and others using fisheye lenses for wide shooting more often. Certain creatures at various distances will still have some curvature and some hate it, some love it and some just accept it versus soft corners. Many learn to use it so well the effect isn't even obvious.

I myself have posted that with today's large mega-pixels in dSLR cameras cropping a small area of water or whatever is OOF (out of focus) is not a big deal in post processing but many feel this is a terrible solution.

Without seeing the type of shots (reef in foreground, main focus a bit farther into the frame?) I don't what to tell you do. Except maybe get a Tokina 10-17mm Fisheye lens and go back and read Alex Mustard's shooting posts with this spectacular optic.

Not trying to be a downer just realistic.

Good luck!

dhaas

Derek,

The Tokina Thread with some great example of what the lens can do is here.

Steve

Derek,

The Tokina Thread with some great example of what the lens can do is here.

Steve

Wow.... I see Alex has done some very nice work here! I noticed some comments in other threads about, "Magic Filters"... Green water, blue water filters for the 10-17mm Tokina... Do any of you have experience with them and do they really work well? I primarily dive in Monterey California and we have a lot of green water here... Also I make it to the blue water areas too...

Cheers

Derek...

Derek,

Try this on http://wetpixel.com/forums/index.php?showt...l=magic+filters

and check out this thread on filters in the Galapagos http://wetpixel.com/forums/index.php?showt...l=magic+filters

Steve

Hey Guy's,

Here's a few shots from the Canon 40D and 10-22mm with 8" dome... These are at 10mm and f6.3, 1/125sec. I'm having trouble trying to figure out how to show text under the photo, so I'll just comment here instead. These are shots inside the Hilma Hooker wreck in Bonaire. The second shot is a 100% crop of the middle and the 3rd shot is 100% crop of the upper left. This is very typical and you can see that 50% of the shot is out of focus?! Yes there are objects in this shot that are not in the same focal depth, but the crops I'm showing are...

Derek...

Here is another set with the 40D, 10-22mm, f8, 1/125s, 22mm. You will notice that the improvement is not much... Looking beyond the reef into the blue is not an issue with this lens, but anything in the same focal plane seems pretty far off. Sure everything looks good zoomed out, but at 100% things get off the mark.. Both the second and third pics are 100% crops of the middle and lower right corner. BTW the two sets that I'm showing have a +2 Diopter on the 10-22mm.

Cheers

Derek...

Derek,

 

After going through a progression of Canon dSLR bodies all in Ikelite housings and using the 8" dome port with both rectilinear lenses (I had a Canon 10-22mm EF-S) I think you are just going to frustrate yourself looking for tack sharp edges with the Canon 10-22mm EF-S lens especially at 10mm.

 

The testing you're thinking of was done by Jonathan Bird, and he was shooting a Nikon dSLR and Nikon 12-24mm lens. His tests resulted in the mid-length extension Ikelite lists for that lens and the Canon 10-22mm EF-S lens you have.

 

Lots of shooters here at Wetpixel have added more or less extension, added +2 to +4 diopters as you have and still are not happy at 10mm with that lens.

 

MY opinion is NO rectilinear lens trying to focus on the curved image a dome port creates underwater will be as sharp as a fisheye lens. Which is why you see so many folks like Alex Mustard, myself and others using fisheye lenses for wide shooting more often. Certain creatures at various distances will still have some curvature and some hate it, some love it and some just accept it versus soft corners. Many learn to use it so well the effect isn't even obvious.

 

I myself have posted that with today's large mega-pixels in dSLR cameras cropping a small area of water or whatever is OOF (out of focus) is not a big deal in post processing but many feel this is a terrible solution.

 

Without seeing the type of shots (reef in foreground, main focus a bit farther into the frame?) I don't what to tell you do. Except maybe get a Tokina 10-17mm Fisheye lens and go back and read Alex Mustard's shooting posts with this spectacular optic.

 

Not trying to be a downer just realistic.

 

Good luck!

 

dhaas

Hey dhaas,

thanks for the feedback. I guess I went through the normal progression trying to improve my setup by trying to understand why the images were coming out the way they did. I was hoping the +2 or +4 would have made a more significant change, but if you look at my attachments on a later post, you will see that reasonable focus does not belong in the same sentence with the 10-22mm and a diopter, unless we view everything from a reduced view. I would have been happy with reasonably sharp, but I'm finding the middle 50% is good and the outter 50% of the shot is just plain bad. I agree with you on cropping the blur out, but when I back off the shot in the water to account for the blur crop, I run into the being to far away for the strobe to work well. I suspect that if we had bigger dome ports, that are more evenly match the lens radius, we would get better results with the 10-22mm type lens.

I looked at Alex's and others work with the Tokina 10-17mm and it appears to be in a different league in regards to the edges. I'm going to give the 10-17mm a try and will report back on what I find..

Cheers

Derek...

Hey Derek,

I see what you're referring to in your crops, although I will confess to not looking at the edges of my photos that closely.

Then again, here's a list of lenses I've shot underwater and why I have become a bit of a Fisheye lens zealot. All the rectilinear zoom lenses never pleased me that much, although I don't know if I'd say 50% of your pictures are OOF.

The worst thing is as you've observed is the closer you try and get with a non-fisheye wide angle zoom for good lighting, etc. the more apparent the edge blur is

When I shot Nikon I shot:

* Nikon 18-35mm ED lens

* Nikon 12-24mm

* Sigma 15mm Fisheye

On Canon I've personally used:

* Canon 10-22mm EF-S

* Canon 17-85mm IS

* Canon 18-55mm "kit" lens

*Canon 18-55mm IS "kit" lens

*Sigma 15mm Fisheye

* Tokina 10-17mm Fisheye

Like Alex and many other APS-C sensor shooters I've settled on the Sigma 15mm or Tokina 10-17mm Fisheyes for my wide work.

Hope this helped you a bit

dhaas