D80 Ikelite housing+Sigma 10-20mm

Hi,

I've been searching in WP and in google but still didn't find a simple answer:

Which Ikelite ports do I need for my Sigma 10-20mm (with Ikelite D80 housing) both options: 6" dome and 8" dome.

I really got "disoriented" with what I've read. Please help, I'll be grateful if someone with this lens could tell me: get this and that ports.

And yes... I know about the no-zooming problem with this lens & Ikelite, I guess I could do without it.

THANKS!!!

Hi,

I've been searching in WP and in google but still didn't find a simple answer:

Which Ikelite ports do I need for my Sigma 10-20mm (with Ikelite D80 housing) both options: 6" dome and 8" dome.

I really got "disoriented" with what I've read. Please help, I'll be grateful if someone with this lens could tell me: get this and that ports.

And yes... I know about the no-zooming problem with this lens & Ikelite, I guess I could do without it.

THANKS!!!

The 6" port is 5503.50

For the 8" dome, you'll need the dome 5510.45 + the correct port body 5510.16

The 6" is cheaper, and smaller, but the 8" will give you better pictures. So you need to decide what's more important to you.

The ikelite port chart is here: http://ikelite.com/web_pages/2port_nikon.html

I don't have that lens but the port chart doesn't say any issues with zooming, so you should have no problems with the zoom.

Hope that helped.

Cheers,

alan

when it comes to superwide rectilinear lenses, the bigger the dome the better. smaller domes create serious corner sharpness issues which can be helped with a strong diopter, but you lose angle of coverage and add another optical element. personally i'd go for the 8" dome. you may still need a diopter with it, chekc ikelites recommendations, but would be a weaker diopter, minimizing the optical shenanigans going on. 6" domes are best left for the fisheyes.

cheers,

chris

I have shot the Sigma 10-20 on a Nikon D200 for years in an Ikelite housing. It works beautifully. Use the 8" port and the port body recommended by Ikelite (the medium length one). You will need a low profile zoom ring and low profile clamp. The fit will be very snug which is in your favor as Ikelite systems tend to have more slop in the controls than the machined housings. You can zoom the entire range and expect sharpness to the corners. You will have to get used to a routine setting it up: Assemble camera in housing without the lens or port on, close back of housing, put zoom ring on lens and push it all the way to the front of the lens THEN put clamp on behind it. Align zoom ring to guides on clamp, then attach lens to camera in housing, push zoom ring down to mesh with housing gears, put dome on camera, find something big to take a picture of.

I forgot to mention, you do not need a diopter, this lens focuses very close. Save the money and don't degrade the image with a piece of cheap glass.

I'll weigh in on this.......

While the Ikelite 8" dome port is REQUIRED for accurate over / under shots many of the rectilinear wide angle zoom lenses (non-fisheyes) perform quite well in Ikelite's extended 6" dome port.

I have used the Nikon 12-24mm and Canon 10-22mm in 6" extended domes plus sold many users the proper length extended 6" dome port for for Sigma 12-24mm and even the 10-20mm lens mentioned here.

The thing I determined is at full 10mm you will see some edge softness no matter what aperture you stop down to, adding diopters or other "solutions". But if you simply zoom to maybe 12mm at a very minor loss of view the edges sharpen up even in the 6" domes.

I think it has to do with the lens angle coming in a bit from full wide plus the exact nodal point of an extended dome port which on a rectilinear zoom lens will never be perfect at ALL focal lengths.

Personally, I think adding a zoom ring and clamp on such a wide lens is asking for a flood.....But I have had some SIgma 10-20mm folks squeeze it in against my (and Ikelite's) recommendations.

I also think zooming versus setting one focal length and concentrating on that view for a dive can sometimes lead people to shoot too far away for good strobe color.

If you want the ultimate in edge sharpness then there's only one lens to use, the Tokina 10-17mm Fisheye. You can "de-fish" the curve seen at 10mm on APS-C sensor dSLRs and at 17mm if used properly it isn't even that obvious.

Just my humble opinion.....

dhaas

Thank you all for your replies, I got a bit wiser..

At first I thought maybe it's high time for a fisheye lens, but I think it would be a bit cheaper to start with a diopter on the Sigma.

Any suggestions as for the diopter: which number/brand?

Again, thanks a lot!

Thank you all for your replies, I got a bit wiser..

At first I thought maybe it's high time for a fisheye lens, but I think it would be a bit cheaper to start with a diopter on the Sigma.

Any suggestions as for the diopter: which number/brand?

Again, thanks a lot!

If you are using the 8" dome there is no need for a diopter. Not sure about the 6" dome but if it is soft in the corners as dhaas claims maybe that would be a poor choice anyway. The 8" dome and zoom clamp assembly is recommended but you need the low profile one #5509.28. It is easy enough to refer to the Ikelite port chart to confirm all of this. Here is the link: http://ikelite.com/web_pages/2port_nikon.html Not sure what above poster meant by risk of flooding by adding a zoom clamp and sleeve, even stating it is against Ikes recommendations. This is not true. Ikelite recommends the clamp/sleeve I have posted here and as I said in my original post, I am going on four years shooting that setup with no floods (no reason to flood?!?) and getting sharpness all the way to the corners. I have never had the zoom jump a gear, which I have had with slimmer lenses. The snug fit is very reliable. The recommendation of the 10-17 was good advice.

Hmmmmmm...........Just checked the latest Ikelite port charts (link listed above) and diverdave1 must be right. Unless I was thinking of an older version Sigma 10-22mm or 10-20mm lens that was too fat to allow any zoom clamp to be used (?????)

Maybe the newest thinner #5509.28 or whatever zoom sleeve has solved this problem.....

I still think (at least from my experience) that zooming in slightly to like 12mm will increase edge sharpness even in the 6" port. It did on my Canon 10-22mm lens....

Or simply get the Tokina 10-17mm Fisheye and you'll never worry about edge sharpness

YMMV

dhaas

I used the Sigma 10-20mm f/4-5.6 for about 2 years in an Ikelite Housing and the required 6" port, #5503.51. Ikelite said that the #5503.51 is almost identical to #5503.50 but bigger bore to accommodate a fatter lens. Ikelite says zooming is not possible. Rather than using the ring, I taped the felt tape in the zoom gear for grip, worked beautifully.

My experience was vignetting at 10mm, rather than corner softness, gone by 12mm. I do not perceive any corner softness in the entire range. There is no need for diopter.

There was once I encountered a free swimming giant frog fish and had to zoom to 20mm to get decent image size, so to me the zoom gear remains essential.

During my last trip I stopped using the Sigma 10-20mm and opted for a smaller package with 10-17mm Tokina FE. Didn't go any comparison but currently I favour the FE.

I used the Sigma 10-20mm f/4-5.6 for about 2 years in an Ikelite Housing and the required 6" port, #5503.51. Ikelite said that the #5503.51 is almost identical to #5503.50 but bigger bore to accommodate a fatter lens. Ikelite says zooming is not possible. Rather than using the ring, I taped the felt tape in the zoom gear for grip, worked beautifully.

 

My experience was vignetting at 10mm, rather than corner softness, gone by 12mm. I do not perceive any corner softness in the entire range. There is no need for diopter.

 

There was once I encountered a free swimming giant frog fish and had to zoom to 20mm to get decent image size, so to me the zoom gear remains essential.

 

During my last trip I stopped using the Sigma 10-20mm and opted for a smaller package with 10-17mm Tokina FE. Didn't go any comparison but currently I favour the FE.

Thanks. As far as I understand the need for a diopter isn't to eliminate the vignetting ,it's to help the lens focus.

Of course a fisheye lens is better, but for me to start with a diopter on a lens that I already own is the only option at the moment (despite all the cons of this setup).

So, you didn't have any problem with focusing?

Thanks. As far as I understand the need for a diopter isn't to eliminate the vignetting ,it's to help the lens focus.

Of course a fisheye lens is better, but for me to start with a diopter on a lens that I already own is the only option at the moment (despite all the cons of this setup).

So, you didn't have any problem with focusing?

Yes I understand that if you want to go the path of the Tokina FE you need the lens and the port - and for the 6" port you need to remove or modify the shade or it too will vignette. I have my shade removed and got some flare when I didn't position my strobes correctly.

About the 10-20mm, sorry I might have confused you, there is no need for diopter for focusing - the lens focus close enough to not need a diopter. No problem with focusing. I was shooting with single strobe, mostly 1/60s or 1/125s at f/8 to f/11 in good lights in tropical Asia waters.

The 6" port vignettes at 10mm. 12mm is the minimum.

Hope that helps.

Thanks Diediealsomustdive and other who helped me. I guess I'll by a close up filter anyhow to try it with and without. I'll report later...