got my sigma 18-35mm 1.8 art lens.

[dannylightning]

EDIT. after spending quite a bit of time screwing around with this lens and the sigma dock i think i finally have it tuned. it was a mess out of the box but with the dock i was able to fix it up and it now seems to be doing a awesome job. ill see how it goes the more i use it. but so far so good after the fine tune.

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up close it seems to be ok focus wise. step back about 5-7 feet and this is what i am getting at the same shutter speed, i am guessing this is because it does not have VR, but than again i could hand hold my nikon 35mm 1.8g at those shutter speeds just fine and it did not have VR

if i go into the af fine tune my camera is recognizing the lens as my nikon 18-200mm lens.



i think this thing is going back to the store.

 

[tirediron]

What shutter speed?

 

[dannylightning]

What shutter speed?

1/40 with the lens at 35mm and 1.8 from everything i have ever read you should be able to hand hold a lens with the shutter speed set to 1/the focal length of the lens. and i know i used that shutter speed on my nikon 1.8 when hand holding at night. at least i am pretty darn sure i did. maybe i am mistaken here.

i boosted the shutter speed up to 1/250 did the AF fine tune which ended up being +13 to get it set right on my other target which has a target and a ruler, i did this on a tripod at f/2.5 and the images are coming out sharp but i need to use a faster shutter speed than i think i should have to be using. maybe i am wrong here.

i have the sigma dock but crap that is complicated, say your doing the adjustment at 35mm you have like 6 different positions at 35mm depending on where the focus number are set. that would take for ever to set up..

 

[tirediron]

In my experience things start getting sketchy below 1/60 - generally most people can hand-hold reasonably down to 1/30, but when you're that close to the target any little bit of movement will show.

 

[dannylightning]

In my experience things start getting sketchy below 1/60 - generally most people can hand-hold reasonably down to 1/30, but when you're that close to the target any little bit of movement will show.

actually the closer i am to the target the better farther away seems a little worse. the free target i downloaded had instructions of how far away to be for the focal length you are using so i go by that. the other target with rules where you want to have 0 dead sharp and the positive and negatives numbers equity bury i am not sure how far away to be with that but it seemed to work ok..

here is a photo i just took of a object after tuning the lens the best i could. the shot is hand held at 1/80 and f/1.8 focus should have been on one of its eyes, cant remember if it was the left or right.

i guess i was just using too slow of speed for this lens plus the focus was way off out of the box. fine tune on all my other lenses have been between 0 and +/- 3 and this one is at +13, that does not seem right.

 

[tirediron]

Might be worth trying another copy.

 

[dannylightning]

Might be worth trying another copy.

yeah, might be, if i need to have that kind of AF fine tune on the lens would you say i should return it, seems to be taking very good photos at the moment. here is one at 18mm and one at 35mm at f/2.5 these look really good IMO no editing done or anything, they seem very sharp.. if it were not for that AF fine tune number i think i would be happy at this point. is that worth sending it back over ?

gonna take a few from farther and way and crop them and see how those look in a few..

 

[tirediron]

If it works, it works, but yeah, that's a heck of a fine-tune index. Do you have another body on which to try it for comparison?

 

[dannylightning]

If it works, it works, but yeah, that's a heck of a fine-tune index. Do you have another body on which to try it for comparison?

no, as of now i just have the D7200, i just took a photo of the same subject with my nikon 18-200mm and well it looks pretty comparable just not as wide of a aperture. looks pretty comparable as far as IQ goes and seems pretty sharp.

i took some pics with the sigma at 35mm standing farther back and it the focus seems kind of hit and miss. took a few different shots and some were nice and sharp, some looked like missed focus. not sure about this lens..

 

[dannylightning]

here is one more shot with the simga on the target with fine tune off as you can see its really missing focus.

 

[jaomul]

Can't really say, but it looks like your room is darkish with a tungsten light, is that correct

 

[dannylightning]

i have 2 of those spiral bulbs in the ceiling light fixture , each bulb is equal to 100 watts and 1,600 lumens. its not really that dark in my room IMO, seems to be pretty bright in here actually, much brighter than the rest of the house.

 

[jaomul]

Fair enough. You need to be doing these adjustment when the camera is working optimal, so bright is good.I've done it recently not using charts, just compared pictures after dial ins etc.

 

[dannylightning]

Can't really say, but it looks like your room is darkish with a tungsten light, is that correct

Fair enough. You need to be doing these adjustment when the camera is working optimal, so bright is good.I've done it recently not using charts, just compared pictures after dial ins etc.

well if i get some daylight tomorrow maybe ill see what happens but none of my other lenses have ever been this off and i check the fine tune in this room.

on this lens if i get out the target with the ruler and the tripod, the number 3 on the negative side of the ruler is what is in focus and the 0 is out of focus. when i do a fine tune in the camera of +13 for this lens the 0 is in focus and the other numbers are equity blury..

my big sigma lens reads exactly 0 when i do this without any fine tune.. the nikon 18-200 was very close with out the fine tune, i have the fine tune for that nikon lens at -3 to get the best focus i can on the ruler. but on this sigma 18-30 i got to have +13 on the fine tune to get the 0 in focus and the other numbers equily bulry, seems pretty bad to me.

 

[jaomul]

Try this (in good to great bright light)

Put a page with small text on a wall or door rigid with tape. Set the camera on a tripod same height as the writing so you are pointing lens directly on the surface, lens is perpendicular to text.

Put lens at 30mm and go 1500 mm between lens and text, focus on live view, take a shot. Now go out of live view and take a series of shots starting at -20,-15,-10, -5,0,5,10,15,20 , but between the shots go into manual focus and defocus shots so the lens has to find focus from oof each time. Make note of what shot equal what adj. Check all photos, on screen or on a computer and see which one closest matches your lives view shot. If you get one that matches your in business at least for 30mm but the fact it's a wide enough angle lens it's probably adjust well enough, use f1.8 for this throughout