Tubes for Canon Rebel

[Greg McCary]

Check this link. Are these tubes a good enough quality to get the job done? I don't care about Auto focus. Or should I go for a more expensive set?
Greg
http://cgi.ebay.com/Macro-extension-...QQcmdZViewItem

[SmartWombat]

Tubes are tubes, no optics.
Where you'll have quality problems is in the lens mounts.
And in the release buttons for those mounts.

My cheap ones from Jessops have really nasty thin metal release buttons and sloppy mounts. But they get the job done and are a fraction of Canon's cost (and of their quality).

The ones in that shot look to have the anti-flare ridges inside the tubes (really cheap ones don't) but the internal matt paint doesn't look too good, it seems patchy. Last thing you want is flakes of paint on your sensor !


Bottom line is you get what you pay for.
I would prefer to be able to look and feel rather than buy over the internet.

[Greg McCary]

The thing that worries me the most is messing up my camera. I know there are small contacts that control my AF. I don't want to put cheap crap on it that will damage it. I am almost ready to just use my old Yashica for close ups. But the tubes for it are a little more pricey and hard to find. But I have more lens options for my yashica. What would be the most used lens on a tube? I have an old 2x converter for my Yashica that I have hardly ever used, I thought about gutting it and making a tube with it, but I am not sure how well that would work...
Greg

[cyberlord]

Those extensions don't have any contacts that could hurt your camera, so you're pretty safe there.

I've been eyeing these myself for my Pentax DL, and for $20 (w/ shipping) even if they are not great quality I think they will get the job done. If you really like macro work, then save up for the good quality ones later.

That's what I'm prolly gonna do. A set of Kenko Pentax AF is $114 plus shipping, and I'll buy those if I like doing macro stuff.

As far as optics go, tubes is tubes, like PAul said, there are no optics in them. I don't see why a gutted converter wouldn't work either. It wont be a precise 9, 16, or 30mm spacing, but it will affect your minimum focus distance which is what you want.

Tim

[Greg McCary]

I didn't think that a tube would have to be a specific mm to work. I wouldn't think anything but maybe going to far with your total length would matter? It might be something to play with, I know 2X converters are pretty cheap. A couple of those might work, as I said I never use the one I have anyway. What would it hurt to try?
Greg

[Loupey]

A tube is a tube (mechanically). But I see that these do not preserve auto diaphragm control. With these newer "electronic" EOS lenses, I don't know how you could even adjust your aperture without the camera being able to communicate with the lens. You definitely would not want to shoot any macro wide open.

I don't use AF (nor AE for that matter) either, but you've got to be able to use a full range of apertures in manual exposure mode. So I would advise against this purchase.

As for gutting out a 2x: I can't see why it wouldn't work. Although a cheap/used 2x is still more expensive than a cheap/used tube. Your EXIF data will also be skewed as the lens data will show that the focal length has already been doubled.

And no, the exact length of extension doesn't matter unless you didn't have a built-in light meter and wanted to perform exact aperture/exposure calculations with a calculator. Extension is just extension plain and simple. But again, you should try to get one that preserves the communication path between the lens and camera.

[mjs1973]

I see that these do not preserve auto diaphragm control. With these newer "electronic" EOS lenses, I don't know how you could even adjust your aperture without the camera being able to communicate with the lens.

I read that this is possible, but I have never tried it. If I remember correctly, you have to mount the lens to the camera body (no tubes) and set the aperture to where you want it. Then hold in the Depth of Field preview button so the lens stops down. Then you have to shut the camera off while holding in the DOF preview button. From what I read, this will keep lens stopped down. Then you could remove the lens, and mount your tubes, and fire away.

It's a big extra step, and not one I would want to deal with everytime I wanted to use the tubes. Deffinetly not a technique to use for fast moving subjects.

[cyberlord]

Another method you might try is a reverse lens in front of your mounted lens.

I taped, with electrical tape, my Canon FD 50mm 1.8 to the front of my Pentax 18-55 Kit lens and took this picture at 1/60 f32 with on camera flash reflected by a sheet of PWP and diffused through a sheet of baking parchment paper. If you were to do this full time an adapter ring of the correct size would be a better choice to attach the two lenses together.

I think I'll experiment with this setup and a light box and see what results.

Tim



Here is a 100% crop.

[cyberlord]

Here's the setup on the last photo.