macro or extension tube?

[achilles1]

Hello all,

I am considering buying a 100mm macro for my Rebel XT to do my tank shots. Guy in the camera shop says I should consider an extension tube for my 75-300mm instead. What do you guys think? The downside of the tubes seem to be that I'm going to either have to decrease shutter or increase aperture to make up for the light loss. Would light loss really be a factor considering I have over a 1000 watts of light burning over the aquarium? lol


thanks

 

[maroun.c]

How about gettng both and then using the extension tube with your 100mm macro?
I played a lot with extension tubes, reversing rings....
a shorter extension tube might still allow autofocusing but to get decent magnification yo uwould use a longer tube or maybe stack tubes over each other and then you would loose that. so it depends on how compfortable you are with manual focusing. I would even manual focus with a macro lens but its different for everyone. Also I would think the 75-300 would be to heavy for an extension tube? it would give you a decent image quality I believe but nothing beats a prime macro lens IMHO.
if you go the extension tube way then make sure you get one that allows metering as it will make your life easier.

 

[Dino]

While it might work zooms for macro work aren't the most ideal. In any case if you did use tubes on the zoom you'd want to keep it at 75mm to get the closest to true macro. If you can afford both - I'd get both the lens and tubes, makes for a spectacular setup that can go beyond 1:1 macro. If only money for one - definitely the lens. If you want to try tubes before jumping on a more expensive lens - a better option would be to pick up something like a 50mm f/1.8 to use with them.

 

[achilles1]

Not sure that it matters, but my tank is 30" front to rear and there are corals growing on the back wall.

I have no problem with manual focusing. Maroun.c you mentioned the weight of the 300mm. Does that cause an alignment issue when using the tubes? The shots will be taken from a tripod.

I can buy both, but I can not buy both at the same time. So, I would need to buy the one the one that would give me the most bang for the buck in the short term. Just to get buy and experiment. I can pick up a set of 3 Kenko tubes for $163 or the 100mm for about $450. $450 sounds like wavebox money to me.

I have a few other lens laying around that I could put the rings on too. I have a 50mm, 2-kit lenses. 2-35-80mm and 18-55mm and a couple others that I can not remember right now.

Should I buy the rings or the lens first? At this point, I am not planning on taking a ton of macro shots, but I do want the ability.

 

[maroun.c]

I would doubt that the tube would allow you to even focus that far at the back. I would get the 100 or maybe a 150 to focus that much back . you might not get 1:1 magnification but at least you would be able to focus. One thing about tubes is that they make your working distance very limited. you will not even see whats beyond a certain distance. when I have the set of kenko extension tubes with my 50mm I can barely see beyond few inches. don't know how it will be with the zoom though. Will be back home in a few days and I could check the tubes with my 70-300 VR to see how much farther away you can work. The kenko tubes are not built as good as Nikon or canon ones but they do the job with my 50mm with or without a reversing ring. I was once told that the pressur of a heavier lens over some tubes could cause them to bend a bit and maybe the contacts would not work but I have never tried to put my 28-105 or 18-200 or 70-300 over tubes. Will try by the end of this week and get back with an answer. One other thing yuo can do is to use a teleconverter behind the tubes as that could give you some more distance. With a 75-300 which I assume is a 4.5 or 5.6? I would think it could cause noticeable loss of IQ as well as some light loss (1to 2 steps depending on which TC you get) so with a slow lense to begin with it could cause the lense to fail to lock focus. then yo uwill have to use manual focus.
Lots of options out there I have experimented with closeup filters, tubes teleconverters and different combinations. I did manage to get very nice images with higher magnification ratios but it was at a price of convenience as it is really hard to focus and meter with a 50mm inverted over a set of tubes. use of a macro rail is a necessity as it makes your life easier, also you need to have a very sturdy tripod, a wireless or cable release....

 

[achilles1]

By working distance, you mean the distance from the front of the lens to the subject right?

What do you mean "I can barely see beyond a few inches" when using the tubes?

Sorry, I'm just a little lost. I really appreciate your help. I've tried to keep my camera gear simple as I like to travel with it.

The 75-300 is the 5.6. So, it's pretty sloooow.

I thought about the teleconverter too. But by the time I buy a teleconverter and tubes I might as well buy the 100mm lens because those items are going to slow the slow lens down even more more than likely yielding lack luster results.

Seeing as how you have done a lot of experimetning with tubes, converters etc.. Is the botton line that I should buy the lens and forget about all the other options?

thanks again. This is just new to me...

 

[bbeck4x4]

I have the 90mm Tamron macro, it is a great lens, with a f2.8 and a 1:1 it is really close to your price range. It also does a great portrait shot. all in all a very sharp lens.

at 90mm it will focus into the tank a bit better than the 50, I'd like to try a extension tube on it, just to see what it can do.

 

[louist]

All the important points have been covered.

Extension tubes will only work for a corals close to the glass, and maybe more if you have a nano tank. For the greatest versatility and convenience, a dedicated macro lens is the way to go. That's what I will get too if I were you.

A 25mm ext. tube will eat up almost 2 stops of light, and even with 1000w MH over your tank, it's still too dark for anything in partial shade.

 

[maroun.c]

By working distance, you mean the distance from the front of the lens to the subject right?

Correct

What do you mean "I can barely see beyond a few inches" when using the tubes?

Beyond that distance everything will be just a blurr. tubes makes your focusing distance very close and also decreases your deapth of field.


The 75-300 is the 5.6. So, it's pretty sloooow.

A slow lense struggles to focus to start with as there is no suffiecient light to get good contrast at focusing when yuo add TC or tubes.

I thought about the teleconverter too. But by the time I buy a teleconverter and tubes I might as well buy the 100mm lens because those items are going to slow the slow lens down even more more than likely yielding lack luster results.

correct but then again you could use the tubes and the TC with the macro lens if you need extreem magnification ratios. it all depends on what yuo intend to do but I guess the best choice and eventually the most favorable to work with would be a macro lens. you could always add tubes or TCs if you feel you need them later which I don't think you really need to.

Seeing as how you have done a lot of experimetning with tubes, converters etc.. Is the botton line that I should buy the lens and forget about all the other options?

If it was me thats what i would do. I bought the TC for some wildlife shots and not for macro initially. Tubes are always a nice addition to a macro lens if you intend to achieve higher mag ratios but I would say that a decent macro lens alone would offer very nice results for tank shots as your corals are not close enough to start with. also tank lighting is not really enough as Louis said.

 

[louist]

Tubes are not really practical when it comes to shooting aquarium pics.

If money is an issue, you can always consider the Sigma and Tamron macro lenses. Optically, they are just as good. Stay away from the 50/60mm macro lenses since their working distance is also very poor. I would recommend the 90/100/105mm ones. You can also pick them up second hand from most online photography enthusiast forums such as FredMiranda.com.

You've received a lot of good advice in this thread. Macro photography is a very different beast to many other types of photography in the sense that gear selection is very heavily dependent on their usability in what you wish to use them for, and that's the difficulties of choosing macro equipment.

 

[achilles1]

Thanks to all for all the help. I have learned a lot. Looks like I will have to drop a couple pennies and buy the 100mm and go from there. Besides "All the cool kids that are taking awesome photos in this forum have one." lol Sorry Nikon guys. lol

Once again, thanks to all that have replied.