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09-23-2010, 12:37 PM   #1
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Wide angle converter

Ok, so I have never used a wide angle converter, or even see someone use one for that matter so I am kind of a noob here. Anyway, I currently have been messing around with night portraits in the city, messing around with the bokeh and what not. I have been using a fairly cheap 50 mm f1.4 lens with my kx. My problem is that in order to keep the background out of focus I must be much closer to the subject than I would like. Now, I know a wide angle converter definitely wont help image quality, but will it necessarily hurt it in the situation I am in? I am a broke college student so the converters I have been looking at are pretty cheap (<$70). I just have no idea how this may distort image quality. Anyone have any experience or suggestions?

09-23-2010, 12:58 PM   #2
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QuoteOriginally posted by turff Quote
Ok, so I have never used a wide angle converter, or even see someone use one for that matter so I am kind of a noob here. Anyway, I currently have been messing around with night portraits in the city, messing around with the bokeh and what not. I have been using a fairly cheap 50 mm f1.4 lens with my kx. My problem is that in order to keep the background out of focus I must be much closer to the subject than I would like. Now, I know a wide angle converter definitely wont help image quality, but will it necessarily hurt it in the situation I am in? I am a broke college student so the converters I have been looking at are pretty cheap (<$70). I just have no idea how this may distort image quality. Anyone have any experience or suggestions?
I have a wide angle converter, and have used it not on a 50mm but on a 24mm to get extra wide. BUT, if you want wider than 50mm why not just get a manual focus 28mm lens, I have 4, the most expensive of which was $30 for a KA mount sigma F2.8, the other 3 cost less than $30 for the lot, and include a tamron adaptall 2 28mm F2.5, a vivitar 28mm F2.5 (M42 mount) and a kiron 28mm F2 with sticky aperture blades. why spend $70 on a cheap adaptor that screws with image quality when you can get a real lens for that price or much less
09-23-2010, 01:38 PM   #3
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hmm, that is definitely something to think about. However, (and I havent actually tried this because I only have the lens described and my kit lens) I read that in general the larger the aperture the greater the background blur. Would f2.5 create significant blur? And maybe I just need to wait longer to find some deals, but I havent found anything affordable f2 or under that is less than 50mm. If you think f2.5 would work for my purposes I would definitely agree that that is the way to go!
09-23-2010, 01:54 PM   #4
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QuoteOriginally posted by Lowell Goudge Quote
BUT, if you want wider than 50mm why not just get a manual focus 28mm lens, I have 4, the most expensive of which was $30 for a KA mount sigma F2.8, the other 3 cost less than $30 for the lot, and include a tamron adaptall 2 28mm F2.5, a vivitar 28mm F2.5 (M42 mount) and a kiron 28mm F2 with sticky aperture blades. why spend $70 on a cheap adaptor that screws with image quality when you can get a real lens for that price or much less
+1. A 28mm lens will give you far better results than the wide angle converter. And as Lowell said, you can find them for very cheap.

**If you can afford ~$200 I would highly suggest a F/FA 28mm. Those are very nice lenses.

09-23-2010, 02:33 PM   #5
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QuoteOriginally posted by turff Quote
hmm, that is definitely something to think about. However, (and I havent actually tried this because I only have the lens described and my kit lens) I read that in general the larger the aperture the greater the background blur. Would f2.5 create significant blur? And maybe I just need to wait longer to find some deals, but I havent found anything affordable f2 or under that is less than 50mm. If you think f2.5 would work for my purposes I would definitely agree that that is the way to go!
I think you are actually going the wrong direction if you want backgroudn out of focus, because depth of field goes up very quickly as focal length reduces.

I might be able to do a couple of comparison shots, beause I can put a WA adaptor on my 58mm helios, which has the required 55mm filter thread, and then take a shot with a 28mm, shooting the helios with WA adaptor at F2 and the 28mm lens at any Fstop you want. I do understand a fast 28mm (faster than F2.8) is hard to come by in K mount but not in M42 mount.
09-23-2010, 03:56 PM   #6
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Yes! That would be perfect if you could do that! I would really like to see if it is worth spending the money on or if I should just try to save up for a decent lens. Obviously the quality wont be amazing, but I can deal with a little quality loss. I guess you get what you pay for.
09-23-2010, 04:14 PM   #7
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Tried a quick shot but some how screwed it up because the magnification was not any where the same even though both were shot from what I thought was the same distance

One thing to note is I did see an extra half stop in exposure Helios is F2 and I used a vivitar F2.5 for the other

The dof and bokeh for the Helios with WA adaptor was so different that I think I need to use a tripod to make sure the framing is correct
09-23-2010, 04:59 PM   #8
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QuoteOriginally posted by turff Quote
I would really like to see if it is worth spending the money on or if I should just try to save up for a decent lens. Obviously the quality wont be amazing, but I can deal with a little quality loss. I guess you get what you pay for.
Actually, in this case, it's kind of the other way around. You can get an 8mm prime for *less* than it would to get a wide converter that performed 1/10 as well. A wide converter that performed decently (but still not as well as a 28mm lens on its own) would typically cost at least 3-4 times what a 28mm lens would cost. Basically, you're better off on both counts getting the 28.

09-23-2010, 05:14 PM   #9
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QuoteOriginally posted by turff Quote
Yes! That would be perfect if you could do that! I would really like to see if it is worth spending the money on or if I should just try to save up for a decent lens. Obviously the quality wont be amazing, but I can deal with a little quality loss. I guess you get what you pay for.
Here is an option for you.

i can give you my 28mm F2.8 M lense. When you can buy wide lense you can return it to me. (you can keep it for year or 2)

Give me your surface address I will see if i could post it to you from Japan or not.


/Arjun
09-23-2010, 06:11 PM   #10
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Well, based on the responses ive been getting it looks like the answer is pretty clear. Thanks for the help!

QuoteOriginally posted by zxaar Quote
Here is an option for you.

i can give you my 28mm F2.8 M lense. When you can buy wide lense you can return it to me. (you can keep it for year or 2)

Give me your surface address I will see if i could post it to you from Japan or not.


/Arjun
zxaar- I guess if these lenses are as cheap as they say it wont be too big of a deal for me to just buy one.
09-23-2010, 07:28 PM   #11
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QuoteOriginally posted by turff Quote
... My problem is that in order to keep the background out of focus I must be much closer to the subject than I would like. ..
If you want shallow depth of field (to keep the background out of focus), you need a LONGER focal length lens NOT a SHORTER one.

So, you would be suited by a teleconverter (eg.g 2x), not a wide-angle converter, nor a wider angle lens which does the exact opposite (and has an even greater DOF).

Another possible all-round option would be a zoom lens, say 80-250mm.
09-23-2010, 09:53 PM   #12
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QuoteOriginally posted by Banjo Quote
If you want shallow depth of field (to keep the background out of focus), you need a LONGER focal length lens NOT a SHORTER one.

So, you would be suited by a teleconverter (eg.g 2x), not a wide-angle converter, nor a wider angle lens which does the exact opposite (and has an even greater DOF).

Another possible all-round option would be a zoom lens, say 80-250mm.


Thats exactly my problem though, I am too far zoomed. I want to shoot the whole subject. In order to fit my whole subject currently with my 50mm i need to distance myself further which makes the background closer to its focal point which increases the clarity of the background. I guess I didnt completely specify this, but when I say I want the background out of focus, I mean completely, as in you have no idea what is going on, all you can see is lights and colors. So, currently I am stuck with either a more in focus background with my subject as I want them, or the background as i want it but zoomed in on my subject more than I would like to be.

And I may still be mistaken on this, but just tested my kit lens (at about f3.5) and my 50mm lens together and it does appear that the greater the aperture the more out of focus the background. Which again makes me wonder, would an f2 or f2.5 be acceptable to keep the background blurred as I want it, because at 3.5 there definitely is not enough blur?

Ha I am starting to confuse myself with this!
09-24-2010, 06:23 AM   #13
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wide angle converter on helios 58mm

ok

here are the shots. Clearly the WA converter does not achieve what I expected.

My converter is marked .48x which I assumed would give me about 30mm when put on my Helios 58mm lens, and be comparable to my vivitar 28mm, BUT see for yourself. Clearly the ratio is not what I expected, and is nowhere near as wide as I expected, but the helios does produce apparently narrower DOF, as well as different bokeh with the adaptor, than a 28mm lens

attached are the 28mm vivitar, the helios 58 with 0.48x converter, and then the shot with the 28mm cropped to the same image as the helios with converter. (Cropped to 60% linear dimension of the origonal shot)

All shots taken from the same camera position (used a tripod)
Attached Images
   

Last edited by Lowell Goudge; 05-28-2012 at 05:28 AM.
09-24-2010, 07:15 AM   #14
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QuoteOriginally posted by turff Quote
Ok, so I have never used a wide angle converter, or even see someone use one for that matter so I am kind of a noob here. Anyway, I currently have been messing around with night portraits in the city, messing around with the bokeh and what not. I have been using a fairly cheap 50 mm f1.4 lens with my kx. My problem is that in order to keep the background out of focus I must be much closer to the subject than I would like. Now, I know a wide angle converter definitely wont help image quality, but will it necessarily hurt it in the situation I am in? I am a broke college student so the converters I have been looking at are pretty cheap (<$70). I just have no idea how this may distort image quality. Anyone have any experience or suggestions?
You've already noted that you understand distance affects Bokeh. I'm of the opinion that the less Stuff you put in front of your lens, the better. As probably also noted, you want to go longer for what you are asking, not wider. With wider, you'll have to get much more into someone's face to keep your background out of focus. I might suggest that instead of going wide angle, given your budget, you find something like an M135 f3.5 or a Super Takumar 105 f2.8. The latter being a little more expensive, especially after you add the M42 - K adapter but you'll get a LOT more mileage out of those two than a wide angle attachment. The 135 is definitely within your budget (in US$ anyway)..

Another option you might consider, if you can swing the cash, is the Pentax A 35-105 f3.5. Current going rate is around $140 and as far as I'm concerned, it's the most under priced lens in the Pentax manual focus lineup.

09-24-2010, 11:27 AM   #15
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Wide Angle Converter

Dear Turf / Lowell & Pentaxian Friends, the WA Converter is much maligned because of some cheap Chinese copies on eBay / Amazon etc.
A good WA Converter is a life saver in many situations, and it need not be expensive.
For the "poor" guy and certainly students, it is a great lens to experiment wide angle photography with. Here are some sample shots by my son, a student like Turf, with his Yashica 0.7X Converter on the 18-55 Kit lens - the Yashica WA & Tele set in 55mm filter mount cost him $ 24 on eBay + shipping.
I note that Turf too has the Kit Lens. So the 18 mm is now a 12mm lens - vow; a true 12mm would cost upward of $ 400 or more.
Note: the photo has been sized for ease of comparison. Img 3570 is with Kit Lens and 3594 is Kit Lens with the Converter.

Last edited by nanhi; 11-19-2012 at 08:32 AM.
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