Hello + quick question about a lense please!
Posted 17/06/2009 - 21:32 - Helpful Comment
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Welcome aboard David!
If you've put the lens correctly on the "A" position, then you should not see the "F--" displayed and shouldn't need the custom setting to permit aperture ring use
Check whether the contacts are dirty and make sure the lens is correctly mounted. I occasionally get this error when using other lenses and find that dismounting and remounting sorts the problem.
Sorry to disappoint you, but with a 28mm lens you are very unlikely to blur the background much, even at f/2.8 You see depth of field is also proportional to focal length - the wider the lens, the more is in focus at a particular aperture... and 28mm for portraits is not very flattering either
Your best bet for portraits is to use a longer lens (even the 18-55 kit lens at 55mm would be ok); find a fairly neutral backdrop and position the person a goodly distance from it.
If you have a looooonger lens (even 50-200) then you'll get even shallower depth of field. But you could end up needing extra lighting, and/or a good steady hand and tripod (plus a subject that can sit still!)
Hope that helps!
Matt
If you've put the lens correctly on the "A" position, then you should not see the "F--" displayed and shouldn't need the custom setting to permit aperture ring use
Check whether the contacts are dirty and make sure the lens is correctly mounted. I occasionally get this error when using other lenses and find that dismounting and remounting sorts the problem.
Sorry to disappoint you, but with a 28mm lens you are very unlikely to blur the background much, even at f/2.8 You see depth of field is also proportional to focal length - the wider the lens, the more is in focus at a particular aperture... and 28mm for portraits is not very flattering either
Your best bet for portraits is to use a longer lens (even the 18-55 kit lens at 55mm would be ok); find a fairly neutral backdrop and position the person a goodly distance from it.
If you have a looooonger lens (even 50-200) then you'll get even shallower depth of field. But you could end up needing extra lighting, and/or a good steady hand and tripod (plus a subject that can sit still!)
Hope that helps!
Matt
http://www.mattmatic.co.uk
(For gallery, tips and links)
(For gallery, tips and links)
Posted 17/06/2009 - 22:20
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Wow thanks for the rapid and very informative response Matt! Yes I have much to learn about technicalities. The 28mm lense comes out at 45mm once on the km. I have a 50mm, sadly without the a setting, which comes out at 80mm, which seems too close. Ideally I just want 50! But I'm certain you know all this. I'll try again with the advice u gave...
Posted 17/06/2009 - 22:39
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also, when i turn the camera on with this 28mm A lense (Sigma) it asks me what lense size it is, so i choose 28mm. an expert in a shop told me it shouldn't ask me - instead it should detect automatically - if i have a correctly working 'A' lense...
any other advice at all??
any other advice at all??
Posted 17/06/2009 - 22:40
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The 28mm lens may be useful for group shots, but 50mm will be better for photographing one or two people on their own. In fact it's still shorter than many would regard as a classic portrait lens.
Since time is short to practice with your 50mm, you might be better off just with your 18-55mm kit lens (if you have one), despite the f5.6 max aperture at 55mm.
By the way, it will save confusion to forget about the 1.5X crop factor and just get used to what each focal length does on your new camera. The crop factor is only relevant when comparing different cameras.
Since time is short to practice with your 50mm, you might be better off just with your 18-55mm kit lens (if you have one), despite the f5.6 max aperture at 55mm.
By the way, it will save confusion to forget about the 1.5X crop factor and just get used to what each focal length does on your new camera. The crop factor is only relevant when comparing different cameras.
~Pete
Posted 17/06/2009 - 22:46
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Matt, you still need to permit use of the aperture ring in the custom setting on the A series lenses or you will just get the F-- flashing ??
Sounds to me that the 28mm you have bought maybe faulty. As Matt says its not contacting with the body properly so give the lens mount a good clean and try again.
EDIT: the A series lenses will always ask for the focal length, thats normal
Sounds to me that the 28mm you have bought maybe faulty. As Matt says its not contacting with the body properly so give the lens mount a good clean and try again.
EDIT: the A series lenses will always ask for the focal length, thats normal
Camera:|K-7|
Pentax Lenses:|DA12-24/f4 ED AL|DA35Ltd Macro|FA31Ltd|FA77Ltd|FA50/1.4|F70-210|FA20-35 f4/AL|A*200/f4 Macro ED|A50/1.7|A50 Macro f2.8|1.7xAF adapter|
Voigtlander|125/f2.5SL Macro APO Lanthar|
Sigma Lenses:|EX DG 100-300 f4|2X & 1.4X TC|
Flashes:|AF540FGZx2|RingFlash AF160FC|
Pentax Lenses:|DA12-24/f4 ED AL|DA35Ltd Macro|FA31Ltd|FA77Ltd|FA50/1.4|F70-210|FA20-35 f4/AL|A*200/f4 Macro ED|A50/1.7|A50 Macro f2.8|1.7xAF adapter|
Voigtlander|125/f2.5SL Macro APO Lanthar|
Sigma Lenses:|EX DG 100-300 f4|2X & 1.4X TC|
Flashes:|AF540FGZx2|RingFlash AF160FC|
Posted 17/06/2009 - 22:51
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dml82 wrote:
also, when i turn the camera on with this 28mm A lense (Sigma) it asks me what lense size it is, so i choose 28mm. an expert in a shop told me it shouldn't ask me - instead it should detect automatically - if i have a correctly working 'A' lense...
No, he's wrong. The camera cannot automatically detect the focal length of even a genuine Pentax 'A' lens, only a more modern lens.also, when i turn the camera on with this 28mm A lense (Sigma) it asks me what lense size it is, so i choose 28mm. an expert in a shop told me it shouldn't ask me - instead it should detect automatically - if i have a correctly working 'A' lense...
Quote:
any other advice at all??
Don't put an "e" on the end of "lens"
any other advice at all??
~Pete
Posted 17/06/2009 - 22:52
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It will ask you for the focal length and you were correct in entering 28mm. Does sound faulty if you have set it to permit use in the menu.
Posted 17/06/2009 - 22:54
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Clarky wrote:
Matt, you still need to permit use of the aperture ring in the custom setting on the A series lenses or you will just get the F-- flashing ??
Not on my K20D when using the lens on the "A" setting.
Matt, you still need to permit use of the aperture ring in the custom setting on the A series lenses or you will just get the F-- flashing ??
~Pete
Posted 18/06/2009 - 00:08
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thank you very much all for your input!
and also for the spelling correction
ok so it sounds like something's not right with this sigma 28mm A i've bought it appears to be clean, i can see the aperture opening and closing when the lense is alone, and the springy bit seems to work to move adjust the aperture too. haha i'm such an ameteur on this forum
looks like i may have to use my back up option of a canon ftb 35mm with a proper 50mm lens for this job on friday then...
does anyone know where i can buy a reliable lens for portraits on my pentax k-m? i'm trying to avoid spending big on any new lenses while on my beginners camera body...
and also for the spelling correction
ok so it sounds like something's not right with this sigma 28mm A i've bought it appears to be clean, i can see the aperture opening and closing when the lense is alone, and the springy bit seems to work to move adjust the aperture too. haha i'm such an ameteur on this forum
looks like i may have to use my back up option of a canon ftb 35mm with a proper 50mm lens for this job on friday then...
does anyone know where i can buy a reliable lens for portraits on my pentax k-m? i'm trying to avoid spending big on any new lenses while on my beginners camera body...
Posted 18/06/2009 - 00:55
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Traditionally lenses in the 85mm range were great for portraits (head and shoulders) whilst those in the 120mm range were great for headshots only (obviously divide by 1.5 to translate this to digital due to the smaller sensor size to get the same coverage).
Use a lens much longer than this and it will foreshorten everything it sees and 'squash' your subjects' faces and noses (although this is great if they have long noses and you want to make them appear shorter )
Use a lens much longer than this and it will foreshorten everything it sees and 'squash' your subjects' faces and noses (although this is great if they have long noses and you want to make them appear shorter )
FILM - Pentax: LX, K2 - 24/2.8, 40/2.8, 50/1.4, 120/2.8, 80-200/4.5, 28-105mm 2.8 macro, AF 280T
DIGITAL - Nikon : D300 - 18-200mm f/3.5-5.6G IF-ED AF-S VR DX
DIGITAL - Nikon : D300 - 18-200mm f/3.5-5.6G IF-ED AF-S VR DX
Posted 18/06/2009 - 07:34
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This is great I'm learning so much on here with all your input.
I'll update my location, which is East London, working in central London
I also just got a 50mm centon or sun lens without the a setting. It would be fine for this job on tomorrow but I'm a bit concerned about spending time guessing at the exposure and not really knowing if I've got a sharp image until I see it on the laptop... I suppose if I set up a tripod and get them all to sit in the same spot I can avoid some of this trouble
Haha I have an offer for some paid work too - I think this is all coming too soon!!
Also, I was recommended a light meter (metre?) in a shop for this, the assistant demonstrated using one manually and his shot did get perfect skin tones. Anyone use one?
I'll update my location, which is East London, working in central London
I also just got a 50mm centon or sun lens without the a setting. It would be fine for this job on tomorrow but I'm a bit concerned about spending time guessing at the exposure and not really knowing if I've got a sharp image until I see it on the laptop... I suppose if I set up a tripod and get them all to sit in the same spot I can avoid some of this trouble
Haha I have an offer for some paid work too - I think this is all coming too soon!!
Also, I was recommended a light meter (metre?) in a shop for this, the assistant demonstrated using one manually and his shot did get perfect skin tones. Anyone use one?
Posted 18/06/2009 - 07:53
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(Meter). You can also buy grey cards which you take an exposure reading from and use this setting. If you are worried about exposure then bracket your shots - take a shot at what you think is correct then adjust the exposure by 1 stop (ie one F-stop or shutter speed) each way.
One word of warning - don't buy lots of cheap lenses - they are cheap for a reason! You may get a bargain, but you will generally do better to try and get the best you can afford. Look for second hand camera shops in your area such as SRS Microsystems where you can try before you buy.
The other thing you should be aware of (if you don't yet) is that the smaller then lens aperture (the higher the number) then the greater the depth of field so the more of the image will be in focus.
One word of warning - don't buy lots of cheap lenses - they are cheap for a reason! You may get a bargain, but you will generally do better to try and get the best you can afford. Look for second hand camera shops in your area such as SRS Microsystems where you can try before you buy.
The other thing you should be aware of (if you don't yet) is that the smaller then lens aperture (the higher the number) then the greater the depth of field so the more of the image will be in focus.
Posted 18/06/2009 - 08:06
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personally I have never heard of this lens and can't understand why you aren't using the kit lens that came with your camera. It has to be better surely? And then you wouldn't be having concerns about exposure etc and at the long end (55mm) would give the same coverage more or less as an 85mm portrait lens on a 35mm slr. It might be slightly slower but just make sure you have adequate light...maybe take the portraits outside instead of indoors?
FILM - Pentax: LX, K2 - 24/2.8, 40/2.8, 50/1.4, 120/2.8, 80-200/4.5, 28-105mm 2.8 macro, AF 280T
DIGITAL - Nikon : D300 - 18-200mm f/3.5-5.6G IF-ED AF-S VR DX
DIGITAL - Nikon : D300 - 18-200mm f/3.5-5.6G IF-ED AF-S VR DX
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45 posts
17 years
i have a pentax k-m dslr. i'm trying to get going with an old lense for portraits but am struggling to make the camera work as it should...
i've just bought this lense - hope the link works: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=17...
its a 28mm with the all important 'A' on the aperture ring. i've locked it to the 'A' setting on the lense ring, then put my k-m on manual focus, permitted aperture ring in the settings (and tried prohibtited as well), but on 'Av' (aperture priority mode) the F stop value seems to be stuck on F4. the screen just displays 'F---' and the light meter doesn't work.
any advice anyone???
i'd really really appreciate it as i got the lense especially for a shoot this friday - i really need shallow depth of field to do portraits for a small charity's staff and blur out their terrible office in the background!
thanks in advance