acrylic vs. glass domes

Hey!!!

I need few opinions to help me make final decision on purchase.

I have Nikon D700 and Sea&Sea housing for it. Until now was shooting with Sigma 15mm in medium size glass dome (Optical Dome Port 7.2 inch).

For the upcoming trips I am about to start using Nikon 16-35 and I think I need bigger dome for it to manage corner sharpness. Therefore I have decided to get a new dome.

Option 1: Fisheye Dome Port 240, acrylic made, 10 inch - around 700USD

Option 2: Zen DP-230 Superdome, 10 inch - around 1900 USD

Price difference is around 1:3

What do I get/loose?

Option 1 Pros:

- 3 times cheaper

- more lightweight

Option 1 cons:

- easier to scratch

- not so good for split shots

Currently I am leaning toward Option 1.

What do you think and what would you advise me?

Note: I am not a pro and 100 dives per year is Mt. Everest to me :-(

Thanks,

Marko

another for option 1- repairable if scratched; and another- easier to pack- I have used an 8 inch acrylic aquatica dome going back to the days of film and lenses that probably arent even sold anymore- the acrylic on this dome has been repolished once and looks like new now and Ive never had an issue with the 16-35 behind it which is the only wide lens I use anymore. I don't personally do or care for split shots so that has never been an issue.

I had same dilema (and have a 7.2" optical dome). I went with option 1 last month and ordered from Yuzo in Japan (380 euro + vat on import).

http://www.uwdigitalcamera.com/store/product.php?productid=16180&cat=273&page=1

The question is: Is anyone able to tell whether a photo has been taken with a plastic or a glass dome? The answer is no... It is much more important, specially with FF and rectilinear WA lenses, to use the right extension rings/configuration.

The question is: Is anyone able to tell whether a photo has been taken with a plastic or a glass dome? The answer is no

This does not prove true for me. I notice my acrylic domes always have little harline marks, no matter how carefully I handle them. My glass dome has remained pristine so far. Usually the acrylic scratches "fill in" when submrged because the refractive index of the acrylic material is close to water. BUT, when I am taking a shot facing a bright source of light, the scratches become visible. I also have better corner sharpness with my glass dome, but I think this is more a function of a larger diameter (9.25 inches vs 8 inches).

One benefit of using glass is that you can coat all surfaces including the inner one with antireflective material. This means less aberrations and less ghost or flare effect

Acrylic domes are usually not coated so that you can polish them however this is also a source of problem if you have stray light coming through the hood at an angle as you will have less contrast and possibly flare

As diverdoug1 says if you have a little imperfection on an acrylic dome when shooting a sun ball this can result in aberrations due to the lack of inner coating above

If money is no object an acrylic dome has no optical benefit however the fact you can repair on the field may be worth something to you together with the fact that is much lighter

I have a Athena 174mm Varidome and the quality is visibly superior of

my Ikelite or Hugyfot acrylic domes, probably also because of it's excellent coating.

Glass domes are much less sensible to scratches, but if you scratch them then they are not recoverable.

Acrylic domes are very sensible to micro scratches from dust or fine sand particles and i had
one scratched by it's neoprene cover during a bumpy boat ride and the weight of a towel above it.

While small scratches can be photoshopped on photos, imperfections of the dome make eliminating them

on a video very dificult and time consuming.

Especially micro scratches on a acrylic dome lead to ugly flares shooting against any light surce.

I am changing my acrylic flat port glass to real glass to see if i can rid of the CA using my 105mm VR.

Hugyfot told me that the optic quality and refraction is better on acrylic glass than on glass, but i will see

how it will work with a glass glass.

Chris

Thanks all, for now I will go with acrylic since it is very small investment and then I will see in in next 2 years where it will get me.

It is really interesting how there is no one unified view on this question even being one of the essential ones.

It may be like a Ford or Chevy question. No one common answer.

It may be like a Ford or Chevy question. No one common answer.

No. It's a Ford or Audi question.

 

No. It's a Ford or Audi question.

That is no questioon at all , I would take the Audi!

I use the Nauticam 8,5" acrylic dome and when shooting towards the sun, it reflects so bad I can see the camera tray in full detail.

I have never used a glass dome and I think I have many sunburst images without any problems... I recently acquired a SAGA 4" coated glass mini dome but I have not tried it yet... we´ll see...

I recently acquired a SAGA 4" coated glass mini dome but I have not tried it yet... we´ll see...

Unless you are much weirder than we think, you'll love it!

I have always been using the acrylic Fisheye Dome Port 240. Underwater i can't see any problem, however when taking split level shots all the small scratches become VERY visible.

So, if you are a fan of split level shots...you might reconsider.

Try

I have always been using the acrylic Fisheye Dome Port 240. Underwater i can't see any problem, however when taking split level shots all the small scratches become VERY visible.

So, if you are a fan of split level shots...you might reconsider.

or try to shoot video against the sun with a microscratched acrylic dome and you will discover at home how much microscratches you have ...
While scratches on a Photo can be relatively easy photoshoped, this job is really hard to do on video.
Chris

Ok guys,

I've read all the discussion, but I don't understand why no one makes the consideration that if an achrylic dome is completely scratched you simply have to change it with a new one! With the price of a glass dome you can purchase 4 achrylic S&S 240 mm.

This is mathematic, no opinion.

This is my 240 on mdx d800 the picture showed the 17-35/2.8 setting. At the time my dome is in good condition and allows me to make direct sunlight picture.

Chris, are you in Orosei in June?

Bye

... I don't understand why no one makes the consideration that if an acrylic dome is completely scratched you simply have to change it with a new one!

 

Because even four acrylic domes don't have the optical properties of a coated optical glass dome? Everything else about perspex is better, but surely that optical quality counts for something?

Yes Tim,

You tell the truth, but I'm not sure that a port like the 230mm Glass super-coated Zen dome can give me a really appreciable quality improvement (compared with the good S&S 240mm). Probably after one or two year of use my acrylic dome will be ready for the trash bin, probably. I'll be happy to restart this discussion at that time!

There is another factor: in any case our systems (dome+ extension) are an approximation. The correct optical "centrature" needs a specific calibration. There are some systems (ie, Seacam) that offers a wide choice of extension rings (with a very complete lens chart) but not the Sea&Sea System, in other words for s&s users this kind of calibration is absolutely approximative.

In this contest the research of the pure highest optical quality could became a Chimera.

But I'm very curious, I'd like to compare a Zen 230 to the S&S 240 on MDX D800 with my favorite lens the (old) Nikon 17-35 using a different set of extension rings.

Ok, I've the housing, the camera, the rings, the acrylic dome, the Nikon zoom and a friends of mine ... the swimming pool

Missing only the Zen 230 Dome for S&S, sorry

bye

Not all glas domes cost 4 times more than a glass dome:
500€ / 690US$ Hugyfot 174mm acrylic dome
790€ / 1090US$ Hugyfot (Athena) vario 170mm coated glass dome

I personally consider a coated glass dome far superior to a acrylic dome, handling and optical quality wise.
If you do video, any scratches or reflections can lead to hard to recover defects on the recordings.

Spanish manufacturer SAGA DIVE has a broad choice of out and inside coated optical glass domes for particular lenses like the
Tokina 10-17, Nikon 10.5, Canon 8-18 and the Panasonic 8mm

Pricese for the domes are 595€ = 821US$

Chris

VBPress: Yes, i will be in Orosei in June as we start dive operation June 1st, but i will be in Switzerland June 13-20th