A Craving For Glass

... Now which extention will I need now from Aquatica. I think one longer one is better than two smaller ones. When will it stop? :shock:

This is not a problem in optics theory. Set your rig up. Get out a ruler and measure how much further the port has to be so the fully extended lens won't hit it.

which model 1.4x TC will work with the 105 and D70 and will still have autofocus?

The Kenko 1.4x for AF-D/AF-S

Thanks to Craig and Craig for the teleconverter info..

Just realized that my Ikelite 105 port will not accomodate the extra 3/4" that a 1.4x TC requires.....I would have to buy a longer port and would be limited to only autofocus.....that would be risky I think, unless the lighting was very good.....thought anyone?

Looks like I'll stick to the Nikon 3T and 4T diopter ( that's nikonian for +1 & +2.9 )....min. focus distance will decrease, but magnification will increase

Karl

Karl,

Why not try manual focus using Ike's excellent MF port for the 105mm? (no extra focus gear required!) It's really not that hard.

I bet if you ask Ike nicely and send him the length of your teleconverter he can make one for you.

Sincerely,

James

Karl, I think AF *only* will be hard to live with at these magnifications. Does your housing support the AF/MF switch? If so you could prefocus and lock it.

Incidently, this was the denise I shot in SWV using the 105mm + 1.4x and 3T with a D100. Magnification is somewhere between 2.5 and 3:1. If you look closely, you will see tiny shimp in the frame (easier on full-res). Total frame height is 8-10mm. This image is uncropped.

Just amazing. Is the shrimp about 1 1/2 inches (relatively) to the right, in line with his eye? That must be the size of, I don't know. Darn small. WOW.

Thanks Craig.

There are quite a few in the frame but they are hard to see in the small version. The most noticable ones are on the seahorse's back, in the upper right corner (inline with the eye, like you say), and about 3 o'clock from the seahorse's mouth. I was told that the seahorse eats these but in my images it looked more like they were cleaners. It clearly appeared that one was swimming toward the seahorse in one of the shots. I think you could measure these in terms of "grains of sand".

Yes, I can see the one on his back, (In spite of what Todd says, I've got pretty good vision). All I can say, I'm glad we're going to Lembeh in a couple of months. Otherwise, your stunning pictures would be prompting me to start twitching ala Clouseau's Inspector Dreyfus...

Rand

Any chance you could magnify one of those shrimpy things? I'm curious as to what they are.

Thanks, Leslie

These are difficult because I couldn't see them and DOF was so shallow. I took some crops from another image that I front-focused. These are a lttle clearer, but they are very tiny and the D100 is a soft camera. Sorry for the oversharpening but it's not going to be good any way you do it. The second image may be two shrimp or it may simply be debris. They looked like they were swimming directly toward the pygmy though. The last has distinct features.

On sharpness: I've found that the Kenko 300 2x softens the image quite a bit. But nothing that can't be brought back to acceptable with PS sharpening.

On ports: Ikelite makes some longer ports and can custom make what you want. I'm not sure about the manual focus version. With the Aquatica, I just pick extension(s) that get me the right length.

On AF vs. MF: With the 2x it is very difficult to AF. Very, very difficult. It can be done, but your subject (and you) must be very still. If your housing allows control of the MSC switch (does the D70 have an MSC switch?) You get it to focus close to where you want, flip to switch to M and move the camera. My old Ikelite film housing didn't control the MSC switch, so this technique wouldn't work.

Diopters are much easier to work with, but suck when you can't get your port close to the subject without the subject moving or bolting.

You can stack the diopters, but you still may have a port length issue.

Thanks, Craig. These transparent bits look like debris & mucus either caught on the soft coral or extruded by the coral itself. I suspect your shrimpies were some sort of 'pod - copepod, ostracod, amphipod, etc - which would be in the right size range for the pygmy's mouth.

Leslie

I personally don't understand why anyone would want to use a 105+teleconverter at any point other than its maximum reproductio ration. At just a few inches farther away from this point, you are shooting what could be captured with the 105 only (meaning a brighter viewfinder, more depth of field, and a sharper image).

Teleconverters have no affect on minimum focus distance measured from the lenses front element. I measure this as just over 5" with the 105.

Using a Nikon 4T dioper will bring this back to 3" IN AIR, or just over 2" in water- hence the difficulty shooting at maximum reproduction ratio. In fact, I'd venture to say that most people using this combo (a TC+105+DIOPTER) aren't capturing images that couldn't be captured with the 105+TC exclusively based upon their distance from the subject.

I have both Tamron and Nikon Teleconverters, and have ordered a Kenko pro 300 in anticipation of keeping it and ebaying the others (assuming its sharpness is better than the rest as I've been told).

My recomendation would be to lock the lens at 1:1 in MF, and don't even install a gear. Focus by moving the housing in and out to find the minimum focus distance. If this doesn't let you get close enough, add a wetmate diopter. With the size of the rig you are pushing around, 2" is awfully close.

Trying to shoot subjects best shot with another lens will lead to lots of sub-standard images and lots of frustration.

RC

That's exactly what I do, Ryan...

I set my 5050 to its minimum focusing distance while on manual focus... hypnotize my subject.. and bring the camera in to a little more than an inch to get the photo in focus. Works for me!

By the looks of this thread, I don't think my addiction to glass is as bad as I first imagined in comparison with some of you guys. Shewww!

Keep it going, guys. I'm learning lots of the good stuff for whenever I decide (if I decide) to move to a DSLR.

You set up with a teleconverter because you anticipate needing more magnifcation than the 105 alone can provide. Otherwise you shouldn't do it, as Ryan says. On the other hand, if you need 1.2:1 then the teleconverter will provide that with greater working distance than the 105 alone. The 1.4x degrades the image but not nearly as much as the the 2x does. DOF at identical magnification and f-stop will be unaffected but there will be some softness and focus will be harder.

The flat port increases the working distance by a factor of 4/3, so the actual shooting distances are a little longer depending on how close the lens is to the port glass. I agree that the 4T diopter is quite aggressive with the 105 because of the short focus. The wetmate diopters have the same problem with prime macros that the 3T/4T do: once you've minimized your working distance you won't get much more magnification out of them. At least you can take them off underwater and that allows higher powers (ala Wetmate).

Ultimately, you need to preserve some working distance when your goal is higher mags and the only way to do that is with longer focal lengths. You choices are teleconverters with the 100/105 or switching to the 180/200. Sigma has the new 150mm coming soon which may be quite interesting (and f/2.8 too) but aside from that the next step up is 180mm. I find that to be quite long with a cropped sensor but very nice with full frame. The big argument for teleconverters is that you don't have to travel with another big, heavy expensive lens. Personally, I prefer the 180/200 and hopefully the 150 when it comes out. The 150, a +2 and a DX sensor would be a nice combo.

I used the 200mm and 6T diopter for the pygmies in lembeh. Hand shake is quite a big problem!

Thanks, Craig.   These transparent  bits look like debris & mucus either caught on the soft coral or extruded by the coral itself.  I suspect your shrimpies were  some sort of 'pod - copepod, ostracod, amphipod, etc - which would be in the right size range for the pygmy's mouth.

Leslie

Yes, some might have been debris with a "shrimp-like" shape. Some moved around though but I couldn't tell if they were shrimp. I only had out-of-focus images to go by since I didn't even know they were there. Some appeared colored and some were clear but I figured that may have been a consequence of the strobe lighting. The locals thought it was "seahorse food".