Ikelite 8" Dome

There is an improvement in image quality.

The article is done but I don't know how to post it on the new Wetpixel. Here's a photo of the back side of the dome that should explain a lot:

And this is what the different extension rings look like:

That one is super-long. The one for the 10-22 is much shorter.

Cheers

James

Thanks James, that makes things clearer.

I was figuring no extension rings, like the other Ike ports, but obviously that's not the case.

James, could you bring the different extensions that you have on the Shark Trip? I only have the one that came with the dome...I'd be intereted in trying different ones

Karl

Gee, I dunno Karl, these are kinda heavy. And after the wetsuit incident...:-)

J/K OK, I'll bring them.

Cheers

James

Thanks James....I'm still embarrassed about the wetsuit

Karl

how does one adjust the zoom range with this Dome ???

Thanks James for posting this info.

So it looks like the extension sustem is on the ikelite end. So what is the chance that the 10.5 can be used in this port if you had the proper extension?

I really think its critical that you can use the 10.5mm in this port. Since I already own ports for every other lens there really is no motivation for me to spend an additional $400 unless:

1) I can reduce my packed volume for the 4 lenses I plan to use in domes by carrying the appropriate extensions (10.5mm 15mm, 12-24mm and occasionally 60mm)

2) I can use it for split levels with the 10.5mm and/or 15mm

3) I can justify the cost since I already need to buy the port for the 10.5

4) Of course if there is a significant increase in quality then the whole equation changes.

So what's the deal, will this work with a 180 degree FE or not? I expect it won't be too long before Sigma or Canon offers one for Canon as well so the problem isn't going to be isolated to Nikon users for long.

It will not work with the 10.5mm....vignettes badly ....don't know about the 15mm.....

Karl

Per Ikelite site, "Dome is positioned for the new zoom lenses like 12-24mm Nikon and 10-22mm Canon. Small wide angle lenses in the 10mm to 15mm range can not operate with this placement. Lenses that utilize our #5503.50, #5503.55 and #5503.80 ports can utilize this 8" dome.

Mounting system placing the dome closer to the housing will also be offered. "

http://www.ikelite.com/web_pages/bigdome.html

Thanks Peter and Karl,

I guess its just that I've just received my Nikon rebate and its burning a hole in my pocket!

From the statement on the Ikelite website, it looks like this may be accomplished with a different extension ring.

James, it looks like for now just one of these is available? The one for the 12-24mm and Canon 10-22?

The full review has been posted:

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

Enjoy!

Cheers

James

Improvement in image quality is an understatement! Look at the vignetting behind the small dome! THe corners are black!!!

I might also add that there is much more vignetting on the brick shots than I would expect from L glass on a 1.6 body. Agree?

Kasey

I see no more vigntting behind the small dome than I see in the brick wall test. Are you talking abou the left hand side of the frame? To me the left side looks more like not lit by the strobe than vignetting....

Yes a L lens on a 1.6x body would be better than that. Perhaps thats why the lens isnt L. And I would expect that all EF-s lenses vignette much worse than a full frame lenses when both are used on crop cameras.

Ignore what looks like vignetting in the photos - that is just bad strobe aiming on my part.

Have you guys actually used the 17-40L? It probably vignettes more (on full frame) than the 10-22 vignettes on 1.6x crop. The 10-22 is excellent - and it's a $650 lens to boot...

Cheers

James

Holy Moly! I definetly have never, ever, not even once, got any black corners like that in any of my images taken with the 10-22mm even at 10mm. Now, of course, shooting in tropical waters I seldom shoot more open than f8. But NO, please anyone who looks at those shots, please do not conclude that if you get the Ike dome you will end up with pictures with black blobs in the corners because that definetly has NOT been at least my experience.

On the above, I wonder what else plays in. I think trobe placement (like James already mentioned) is a big one. Was the port turned correctly (with the shade petals inthe right locations)?

Seriously: You really need to be very careful when you present info collected in this manner as "evidence" or this type of ad hoc testing as scientific or correct. It's one thing to do it in your backyard pool and discuss with your friend down the street, quite another to bring iot out on the internet like this. Wetpixel is a great site, it has grown alot and you have a good part of the uw photographer population checking in here. So what you say or claim might have a pretty significant impact on the company whose products you are 'testing". I am saying this with the disclaimer that I do very much believe in an open forum for discussion without pressure from brand x,y or z. And were not out to "cover up" for anyone. However we cannot just go out and make claims about soemthing and base that on shaky evidence. But just keep in mind that while heresay is easy to dismiss, ppl might be less critical of something you pass off as a "test". When you do that, you really do have take reponibility for your methodology and conclusions.

Sooo...Now that we have had the "wiseman report", I would be interested in, to get some balance to this discussion, to get more info about Ike's tests. I don't know if they have actually conducted these or not, but if they have, and from their site it sounds as they might have either done tests or have some other empirical material, it would be wonderful to hear from them as well.

We have heard some less than scientific claims (Sorry Kasey, just putting the dome to the sun and eyeballing the light, doesn't seem to drop 1/3 stop light when I look thru my dome. Could be that your eyes are more light sensitive than mine, who knows). Those claims could be right or wrong, but until tested in a controlled situation where you have all factors controlled and are able to measure them, they are not proven one way or the other.

James did write in conclusion that it is hard to draw conclusions from his report. Good. But in his post he wrote that there is a difference. Hmmm...

Marjo

Well - there is considerable (severe) vignetting on the wide open shots of the brick wall. It is reduced at f8. It looks too severe to be real, but how else would you explain it?

I can see from the "picture of the author" shot that you may have missed altogether with the left strobe, but even the upper rt and lower rt corners are dark - these should be in the hottest part of the image. The amount of vignetting may be caused by the lens itself based on the brick wall shots, but at f10 I wouldn't expect this.

We have heard some less than scientific claims (Sorry Kasey, just putting the dome to the sun  and eyeballing the light, doesn't seem to drop 1/3 stop light when I look thru my dome. Could be that your eyes are more light sensitive than mine, who knows).

Marjo

<{POST_SNAPBACK}>

I wouldn't make this claim looking through only glass, or only acrylic. I make it by direct comparison side by side. I could meter behind both for argument sake, but I'm not really interested in "scientifically" testing something that is so obvious to the naked eye. I thought we were beyond the glass vs acryllic arguments in this post, anyway

My challenge - find me one avid uw photographer that switched from glass to acyllic and prefers acryllic! The biggest pro-acryllic advocates haven't experienced anything else - kinda tough to be objective.

PS - I really wish acryllic domes met my needs, glass is heavy on the arms and on the wallet

Hi,

I used one strobe placed about 12" above the port in the plane of the lens. Naturally, since the strobe is about 12" from the plane of the linoleum and 12" above it, it's simply not capable of lighting the whole frame - and it's not supposed to.

I thought I clearly stated in the review that due to the dark conditions in the pool, I used a strobe. In fact, I said I used 1 DS125 strobe. Since a number of our members were confused by the review, I'll go back and edit it to be more clear. I can see that I provided this information in a photo caption, and the caption shows me holding a housing with 2 strobes on it.

I stated what I did, how I set up the equipment, and the results I obtained, there's nothing ad-hoc about it. It shouldn't reflect poorly on Ikelite, if the lens has a vignetting problem in air that's not their fault...lol. The underwater portion of the review shows that the 8" dome yields sharper photos - it never mentions vignetting.

All I can do is tell you how I performed the test and show the results. It''s interesting to see how the members draw conclusions and what aspects y'all focus on. It teaches me a lot about my writing, and how to improve it, thanks.

Cheers

James

You never mention vignetting - but your pictures show it!!! As a reader I look at the images you provide and correlate your interpretation with what I see. The Ike strobe should have been in the same position, on the same power setting for both close up pics. How do you explain the dramatic difference between the 8" dome and the 5" dome?

Marjo,

I think it has been stated very clearly by James under which circumstances the shots have been made to prevent wrong interpretations. The results don’t claim any vignetting review issues. I understand the test has been focused on something different (corner performance in terms of resolution/shrpness/CA). Providing procedure details leaves the required room for readers drawing their own conclusions and priorities when choosing a certain dome for a certain lens. In my opinion the very useful information provided by James’ tryout does not draw biased conclusion for or against any brand. But it provides very valuable information you won’t get elsewhere before you buy one of the two available domes.

But if vignetting is an item to be discussed here to you - James has provided f-stop data as well.

Acrylic vs glass:

You have stated there would be no evidence to find when it comes to difference in terms of contrast. Well, beside optical physics (light absorption characteristics of different materials) tests have been conducted by several housing manufactures in the past. I have an old book providing information and results on this topic. If I find some time and it is of serious interest to you I can scan some stuff of it and pass you an email as I don’t want to post scanned book pages.

Julian