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Old Feb 11, 2012, 10:27 PM   #1
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Default wide angle makes focus out of range?

I just got a promaster Digital Axillary Wide Angle Lens which is a 58mm 0.7x front mount wide angle lens as part of a lot of stuff. I looked for information and or reviews about it and saw 2 different places where people said that there camera could not focus with it. One was the only review on amazon and I can not seem to find the other again but it was a similar complaint (so its not just me or my lens). I discovered some strange behavior. I tried it on my pentax ist-ds (dslr), with several different lenses. With every lens, with the wide angle attached to the front, I could not focus (auto focus or manual focus) at any distance. I noticed that as the lens moved towards the infinity setting, things were coming closer to focus but at infinity, every distance was still out of focus. I couldn't find my macro tubes, but I have 2 lenses that have a built in macro ring that pushes the lens forward about 10-12mm. One lens would not focus at all but moving it into macro mode made it closer (I didn't try playing with every focal range etc. so maybe it might have worked). On the other lens, moving it into macro mode brought the lens into focus range.

In other words, this lens is having the opposite effect of a macro lens, pushing the whole focus range past infinity. It takes a very strong macro lens just to be able to focus at infinity. I actually though of a use where that might be valuable, and it effectively cost a couple of dollars so who cares if it works, but I'm still at a loss for why the lens is like that. I'm sure I would have been a lot madder if I was one of the people that spend 100$ on this lens. Does anyone have a clue? Is it defective (and apparently others have got ones with the same defect), or would a lens like this work normally on any camera?

Here is the link on amazon
http://www.amazon.com/Promaster-Digi...pr_product_top
And a link to it on wolfes camera, who specifically states it works with a dslr
http://www.wolfes.com/eshop/cart.php...ategory_id=465

and the manufactures page (I think, it seems at the moment promasters site is having issues)
http://www.promaster.com/products.as...230&SubCatID=9

If their site were working I might inquire about the problem just out of curiosity.
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Old Feb 12, 2012, 2:49 PM   #2
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G'day Richard

Sorry to hear about your misfortunes with this lens - while I don't have this exact one, I do have an 0,7x W/A attachment that I use from time to time

Some thoughts ...
1- with the camera lens in place and at 1x zoom / 18mm, focus on infinity [let the camera beep 'ok'] then switch camera focus off [ie to manual]. Now you know that the camera is focused on infinity and all else should follow
2- if you hold the attachment close to the camera lens & move your hand forward / backward does the aux lens focus at all?

What I'm pondering is that the aux lens might need a tiny bit more distance between the filter thread & itself in order to focus - if so then maybe a combo step-up + step-down ring might give this distance

If the aux lens will not focus at all then there's something wrong with its inherent design

ps- I also cannot get your link to promaster to work either
Hope this helps a bit
Regards, Phil
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Old Feb 12, 2012, 4:58 PM   #3
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I have a few higher magnification teleconverters than need to be a few inches from the front of the camera so I know what you mean. With the camera set at infinity, the lens stays way out of focus, even with the wide angle converter moved as far as a foot out (I did start it right at the lens and slowly move it away). I did find an auto focus lens that has very good macro abilities, that can focus the full range with it on. The thing is, focusing at a few hundred yards, the lens is set to focus at about 1'. For that matter, the lens stays around 1'. This macro has a wide range of movement for macro focus. About 80% plus of the focus rings travel focuses from less than 0.3 meters (the lowest marking but it will turn about 1/4" past it) to 1 meter. In other words, it moves about 30 degrees rotation to go from minimum focus to 1 meter, and only about 10 degrees rotation to go from 1 meter to infinity. Without the converter, and the lens set to minimum focus distance, it focuses about 5" away. With the lens focused at minimum focus distance, and the converter on, it focuses at about 1.5'. With the lens and converter focused at a couple of hundred yards, the lens is just past the 0.3 meter mark (about 1/3 the way past the 0.3 meter mark, about 2/3 before the 0.35 meter mark).

I have other wide converters and only effectively paid a couple of dollars for this one (if you consider the value of the other stuff I got, this one was more like free). I just found it very bizarre behavior. There are no problems with the image quality (what you would expect from a cheaper lens). If the image quality was much higher, I would actually have great use for it as is (I still might have a little use for it as is).
I'm just curious. If its defective or mis manufactured, there must have been a whole bad production run or something as others have had similar problems.

I think I'll try contacting promaster to see what they say. I could care less about getting the lens replaced (it wasn't from an authorized promaster dealer so if I am not mistaken, they will not honor any warranty). I think I would rather have it as is anyway. Wide converters are easy to find, beyond infinity adapters don't exist. It might be of some use with some custom lens work I am doing (it would defiantly be of use if it were better quality). I'm just curious what they will say.
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Old Feb 14, 2012, 5:43 AM   #4
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Promaster said they were not aware of any issues. They recommended I take it to the nearest promaster dealer to get it looked at and gave me their information. (got that response pretty quick). I sent them another message, about how I already called that dealer, and they tried a new one off the shelf, and it had the same problem. I haven't got a response yet (I think that might have made it a little more challenging to answer the question). It seems this problem has been around for a while though, so it's strange they hae not hear of it, unless nobody buys these?
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Old Feb 14, 2012, 1:29 PM   #5
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G'day Richard

mmmmmmm ???

Regards, Phil
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Old Feb 15, 2012, 11:15 AM   #6
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I guess I pretty much have my problem worked out but in case anyone else interested reads this. Promaster told me that it was incompatible with the pentax line of cameras, and it was only compatible with certain cameras. This seems to conflict with the product information on their site that says it is good with any dslr. I also called the dealer that it didn't work for, and they said it didn't work on a nikon d5100 with a 55-300mm lens. I discovered it worked fine with my pentax 18-55mm kit lens. That kit lens can focus to about 3 inches though. It seems the lens does have an effect opposite what a macro adapter would do. It also seems it works fine on lenses that have very strong macro capabilities (which my pentax kit lens does). Basically the macro focus of the lens counters the anti macro focus of the wide converter.
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Old Feb 15, 2012, 2:01 PM   #7
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G'day Richard

I'm rather suspicious of the Promaster response
I will PM you for further discussions

Regards, Phil
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Old Feb 15, 2012, 6:47 PM   #8
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@Ozzie_Traveller, not sure if you got my pm, it doesn't seem to be sending for some reason?
anyway, here was my responce.
I tried to send a message earlier but I don't thinnk it sent (maybe the forum doesn't like opera). Promaster is an american company so its no suprise you haven't seen them there. The converter does act like a wide angle should in that it basically zooms out to a 0.7x magnification.

As far as the macro, I'm not sure how knoledgable you are about cameras. Macro is just the ability to focus with the camera very close. Basically a camera like your Lumix can only focus so close. For instance, one of the lumix models can focus to 30cm at the wide end and 200mm at the telepoto end. That means you can not get the camera any closer than that and focus. If you were to take a macro converter/macro adapter and put it on your camera, you can get the camera much closer to something and be able to focus. You would not be able to focus to infinity anymore as the macro adapter shifts the whole focus range. For instance, you might not be able to focus on anything further away than 50 meters with a particular macro adapter attached.

This wide converter is doing the exact oppisite of a macro adapter (its not suposed to but it does). It is shifting the entire focal range in the oppisite direction. When I refer to a macro lens, I am just refering to one that can focus very close. My pentax 18-55mm can focus with the camera maybe 10cm away or closer so it is a macro lens. slr lenses have a distance scale on the focusing ring. If you set it to 10 meters, objects 10 meters away are in focus. With the promaster wide angle attached, with the camera focused at a couple of hundred meters away, the focus ring is reading that the camera is focusing about 0.3 meters away. It has shifted the whole focal range, kind of oppisite what a macro adapter would do. Many slr lenses are not macro lenses, meaning they can not focus with the camera very close. Most of mine can not focus any closer than 1-2 meters away (some long telephoto lenses even further than that). None of these can focus at any distance with the wide angle lens attached. Only the lenses that can focus very close have the range to counter the effect of the wide angle lens.

I have maybe a half dozen wide converter and maybe 2 dozen teleconverters. this is not normal behavior for one. My best guess is that they developed the lens themselves or something (old but smaller company with limited resources), and it worked with the few lenses they tried (which happened to be macro lenses), so they thought it was good. Perhaps they didn't do their research on how a teleconverter is built, they just made one and came up with their own ideas on how to do it? I really have no idea. Promaster has been selling many diffrent lenses for decades, but the do not make any of them. they get lenses from sigma and similar companies and slap their name on them. The only thing I know of that the probably manufacture are flashes. Maybe they tried their hand at actually making a lens and this was what they came up with?

The whole deal about not being pentax compatible it a load of crap. the camera store I talked to tested on a nikon dslr. I'm guessing they didn't have a real answer and didn't know the real problem.

Ultimatly, this converter is only compatible with macro lenses.
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