Newbie to Macro - Have miscellaneous magnifying glasses

[zhollett]

Hi, Im hoping that someone can share their experiences / wisdom with me. I don't have good equipment but I love to tinker. So here goes.
I have a Sanyo Xacti HD1-a video camera that actually takes not bad macro shots. It has a manual zoom which allows the object to be ~1cm from the lens and still in focus. (example below)
Next I have a couple of magnifying glasses which came out of an old Projection TV (pictures below as well)

Using the magnifying glasses, I thought I could just place 1 in front of the other and really zoom in on an object. The problem is that my shot is marginally larger than what I am able to accomplish with just the manual macro mode on the camera without the magnifying glass.

My setup is such that I have the camera mounted on a tripod and I am using my counter top as the "rail system" with my subject on one side and the camera on the other. I have about 2 meters to work with as far as overall length I can work with.

so it goes:

Camera -----------> magnifying glass ----------> magnifying glass ----------> subject

With just the camera, I was able to capture this shot in macro mode: (the sticker is 1.3cm wide)

Since I was using that as a "control" photo, I next started with the magnifying glasses (I have 2 of these):

I then moved them back and forth to try my best to get a good magnification of the subject.
below is the best I was able to achieve.

I tried having the camera on full zoom and full wide, and all the iterations in between.
I moved the magnifying glasses back and forth in pairs and independently and was still unable to get what I thought I should be able to with the setup.

What I am looking for is to have a conversation with someone who is knowledgeable in working with ... less than professional equipment and seeing what can be done.

I will answer questions to the best of my ability. I am very interested in getting this working.

Thankyou for any assistance you can provide.
Zach

 

[Judobreaker]

I do not have any experience working with 'less than professional equipment' like this, however I do have a decent knowledge of optics.
The lenses you are using are probably far from ideal.

First of all what you're going to have to make completely sure is that your magnifying lenses are completely and entirely in line with your other lenses!
If you do not have this straight the image will always look distorted in one way or another.
Look at the picture you took for example, there is some sort of blur on the right side of the image. I believe this distortion is mainly caused by the fact that your lenses were not in line with the camera optics but actually moved or rotated slightly to the left.

Besides their positioning these lenses were also not made for this kind of use.
Their optic qualities may not be the best, but the again we already agreed that this is not professional equipment so you might not have that much of a problem with that. ^^
Stacking these lenses together however increases any optical problems significantly, any distortion you get from the first lens is then again distorted in the second.

I think the best thing to do here is try with one magnifying glass first. Get that glass positioned perfectly in front of your camera and see what the results are.
If the results are anything good you can then use the experience you got from the first try to place the second glass in front of the first one.

I'm not entirely sure if this is going to work as good as we'd like it to, somehow I have a hard time picturing the entire optical setup in my head but it might just need a little time to settle (it usually does with me ).
If I get any good ideas I'll share them of course, I'm kind of curious as to how good this is going to work.

 

[zhollett]

Thanks for the nice information.
I would agree that the lenses are very far from ideal. I saw there was some blurring in the picture and did chalk that up to not having things aligned properly.

Im going to play around with it some more and see what I can come up with.

Where my question was leading (i forgot to ask it directly) is I expected much more magnification, it looks as though I am only getting a 1.5x with the 2 lenses stacked.

I will try some more and see what I can do. Any more insight you think might help would be appreciated.

Zach

Edit: One more thing I noticed with these is that each one looks to be made of 2 pieces of glass sandwiched together in the black housing. I wonder (and am probably correct) if they were cut to the exact curvature required to make the projection TV crisp and clear at a specific focal length... Im going to take one of them apart to see what happens if I change the distance between the individual lenses that make up each lens pack.

 

[zhollett]

Here is how I have things setup (for reference)

 

[Judobreaker]

Yes I think it is quite safe to assume these things contain multiple elements.
More advanced versions usually allow you to focus by changing the distance between these elements (just like what you're used to on a camera lens) so I assume changing the distance between the elements will give you a different focus.

This brings us right to your original question: You expected more magnification.
If these are fixed lenses that means there is one focus point. If this focus point is too far from your lens you simply can't go any bigger.
It's just like with normal and macro lenses. Basically the only real difference between a normal and a macro lens is the closest focus distance.
If you have a 105mm lens which can focus closest at 100cm this will give you a lot less magnification than a 105mm lens that can focus at 30cm, even if the rest of the lens is entirely the same.

If you figure out how to change the distance between the elements correctly and this works well it is quite possible you can achieve a lot more magnification.
Again I can't really promise anything as the optics might very well be optimized for that specific focus distance (they probably are).
It may be worth a shot though.

 

[zhollett]

Well, after taking one apart (read: cutting the plastic housing i half), its made up of 2 different pieces of glass. Different in the fact that they have dissimilar convex curves. One is more pronounced. Individually they do work as magnifying glasses so its not a total loss. (Summer is coming, time to teach my boy about the combination of Sun + Magnifying Glass + Wood)

Separating the distance between the 2 halves does indeed give me greater magnification but at a very steep cost, the "viewable" range of the glass drops from 100% when at normal distance to approximately 20% just in the middle.

The outer edge of the glass goes completely blurry the further I move the 2 pieces apart, and I'm only talking a maximum of ~4cm or so.

I think this spells the end for me using these as a homebrew macro lens. They just don't have the correct optic properties to do what I need.

I am still interested in creating my own macro lens with my boy but I think the rub here is getting glass that has the correct properties.

 

[Judobreaker]

Too bad you don't have a the polishing equipment to make your own glass eh?
I actually learnt how to polish optics at school (and it is damn boring xD).