glass vs. acyllic for photography

[gregr]

hi all-
i've always had acryllic tanks and i know how easily they scratch and how that affects my pictures but i'd love to hear from people that have glass tanks- and if anyone has photo experience with glass and acryllic tanks i'd really love to hear any comparisons you could make- pluses and minuses for each.
basically i'm just wondering if i'd be better off with a glass tank.
thanks,
greg

[TS]

Greg, I can say hands-down glass is better to shoot through. I've shot nothing but glass, then was hired by SMiller to do a tank portrait.

I didn't even think to ask if his tank was acrylic.

I took a ton of shots I was really happy with, but let's just say me and the healing brush in photoshop got REALLY well acquainted over the next couple of weeks while I was editing his pics. I actually enjoyed the process very much, but would have cleared some extra time in my schedule had I known what I was in for.

For probably 60-70 "keepers" I spent about 20 hours on healing brush alone. Of course, my goal is to have an image that's printable to 11x17 so I really got in there at 100-200% and went after every single scratch.

I also probably lost 10-15 keepers due to scratches at the substrate level I couldn't fix.

One thing to certainly avoid with glass is a bowfront tank. My main tank is a 46 bow and my 100mm macro will accept nothing less than a 90-degree angle to the glass- Otherwise, I get zero focus no matter what I do. Shooting my 29, I have that problem below 60 degrees or so, which is pretty extreme for what we do anyway.

HTH.

Travis

[gregr]

yeah i know scratches really stink. i'm also wondering about optical differences. i've heard that acryllic is actually better optically but i don't trust the source 100% as it was an acryllic tank manufacturer
greg

[moflow]

Originally posted by gregr
i've heard that acryllic is actually better optically

i believe that acrylic is clearer ("optically better") than glass, but in my experience that hasn't had much effect on picture quality.

like you said, the scratches are the real problem. i try to buff scratches out of the area i'm going to shoot relatively soon before i take any pics, but i still end up in photoshop when i'm done.

i second what TS said about shooting through bows. i had a bow for a few months but ended up getting rid of it, partly because I could never get a decent shot unless the subject and camera were both perpendicular to the glass. good luck.

[TS]

Hmmm optically... well, it's really hard to tell without a scientific side-by-side, which we'll never get... same specimen, same distance, same lighting.

But the fact that you'd have to go to those measures to see a difference if any tells me that it's probably not noticeably different.

I didn't notice a difference overall.



Travis

[gregr]

hmph...
well, i'm trying really hard to talk myself into a new tank
i have one bad scratch right now- which is not that big of a deal but it's right in front of my anemone/clownfish and that keeps me from photographing them.
greg

[KevinM]

Back in WWII, the navigators "bubble" in the big bombers was made out of acrylic. They'd use their sextant looking through this bubble, so it HAD to be clear, and have as little refraction as possible.
Whether this makes a difference in our photos or not, I have no idea, but I thought I'd toss this out there. I'm about to frame up a 120 acrylic. I've never had an acrylic tank before, so I guess time'll tell whether I like it any more than glass.

FWIW,
Kev

[gljjr]

FWIW,

I would never buy another acrylic tank. They are just too much of a PITA. We have one that is so scratched now you can't even see through the front of it. I'm trying to talk the wife into letting me replace it with a glass one. My 150 glass tank on the other hand is so easy to clean with the magnet scraper and I never have to worry about scratches. In my nearly 40 years of owning glass tanks I've never complained about them.

[Snail Guy]

Scratches alone is one strong argument against acrylic.

No one mentioned that acrylic tanks tend to distort over time. It is very evident on my 65g. I generally don't mind and still like acrylic tanks as they are wonderful.

With those two points in mind, I lean towards glass as the better choice.

A little more to add but far less conclusive...

I often like to shoot close-ups through my aquarium at an angle, either to alleviate reflections from flash or for composition. With this in mind, as you increase that angle, it appears that image quality deteriorates more quickly through acrylic than with glass.

In a recent close-up image through acrylic at angle, I noted a little bit of chromatic dispersion. That is, there was color separation, just as you see when white light passes through a prism to produce a rainbow. It's very subtle but certainly there. Here's a link to a highly magnified portion of that very image to demonstrate my point.

http://www.guamcell.net/~babela/bobs...dispersion.jpg

All substates are subject to this phenomena, glass included. It most certainly has to do with the material properties, specifically the index of refraction. But before I can reach any conclusion, I need to do a little more research, comparing this property between glass and acrylic.

There may be other factors involved, including my scanning process (35mm slide to digital image). I doubt this one however, it appears to be unique to this particular image.

So I have to run a few more tests. Be curious to know if anyone has more to share on this.

Cheers,
Bob

[gregr]

hi Bob-
aside from the scratch issue this is the most important thing. there could be some color cast issues but that [usually] is easily overcome with photoshop.
with acryllic you have to be straight on for close-ups, but my experience with glass tanks (very limited) showed me that the same was true-- move off center and the image goes soft. it would be great to know if one is better than the other for sure though.
thanks for you thoughts- i'm eager to hear what you learn.
greg

[deacon hemp]

i only keep nanos but i have a glass and an acrylic,and my glass shots are always better.if u angle a shot on the acrylic it distorts,glass is less evident for this imo! hope this helps any!

[gregr]

that does help- thanks a lot.
greg

[MalHavoc]

If you're looking for crystal clear quality and scratch resistance, and you're deeply into tank photography, you can't really beat starphire glass, if you can get it. Sure, it costs more, but it's worth it if you never have to airbrush a scratch out of a picture in photoshop again

[gregr]

hah! deeply into tank photography... yeah- that be me
i'm going to look into the Starphire tanks because i really do take lots and lots of pictures of all my little friends and so many of them hang out right at the sand line. i just walk away from a shot that has scratches- cloning them out is too much of a hassle. luckily for me most of my coolest critters hang out right in the front middle of the tank so i get many chances at the cool photo ops.
like this

[moflow]

that's a great pic gregr

[lexusboy]

If you want scratch resistant and clear get starphire, do a search I have heard they are awesome.

[DNA]

I think the plastic is usually thicker than glass for a given size of a tank and the thickness bends the light more at an angle giving you less usable pictures.

Starphire is fine, but think about the transparency of the water wich kills the clarity of the pic quickly if it is not crystal clear.

[gljjr]

Greg, et all.

I look at it this way. If acrylic was so much better optically than glass why are all the top Lens makers using glass?

I agree with DNA in that most acylic tanks are thicker than glass and that is the basic difference when getting off the plane of the glass when taking pictures. Remember the walls of the tank follow the same rules as our lenses. So if the tank is bowed out the picture will not be as clear due to the light refracting off the angled wall of the tank!

The LFS near my house has a 120g Starfire tank sitting right next to a normal tank (both empty and for sale). The only difference I can see is that the non starfire tank glass has a green tinge to it that the starfire one doesn't have. What I don't understand is why the glass costs more. I'll have to check with the glass shop and see what thier take is on it.