What am i doing wrong to get this focused?

Ganoderma

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i use cannon eos kiss x. just bought a new lens. Sigma 70-300mm 1:4-5.6 macro.

so far i have been shooting with the standard kit lens 18-55mm.

i will admit so far i have just been messing with autofocus cause i honestly cant do manual with my eyes.

this is under a cloudy but bright day. these are flower buds. i was shooting on a tripod with a remote to be sure there was no shake at all.

this example is is 1/5 sec.
f/22
300mm
iso-200
exp. comp. 0

any tips?

not cropped but resized
lens1.jpg



cropped and not resized
lens2.jpg


see how out of focus that is? why? i tried about 20 pics at different distances from 4 feet away to 15, and this was the best... :(
 
1. On a crop sensor, diffraction at f/22 is horrendous. I don't go past f/16 unless I desperately need that extra DoF.

2. 1/5s is way, way to slow to handhold a 300mm. You need to get that shutter speed up. Open the aperture to something more reasonable like f/8, or even f/5.6. That will lessen or eliminate shake, and I'm talking about shake from the mirror slapping up and other vibrations. And, let you get down to ISO 100 for cleaner images.

Also, familiarize yourself with this page. Apparently that lens isn't very sharp at all at 300mm, particularly around the borders. Meep.
 
hehe, ya was on tripod and remote so i didnt touch the camera. i never knew the camera would cause so much shake itself, good to keep in mind!

thanks for the link, i wont lie, i need to look up about half those words lol.

but i have another Q. if using a tripod and remote or timer, why is 1/5 too much? i understand 300mm makes everything more sensitive, but does the camera/lens make that much movement for it to cause shake?

thanks a lot for the pointers!!!
 
It can cause some unsharpness. Truth be told I wrote that before really considering the tripod and remote, but it's good to know anyway. If you want to eliminate shake, you've gotta dig-in the tripod if it's on a soft surface, and set mirror lock-up to on in the custom functions. Just go through the custom functions in the menu and you'll find it. It'll lock the mirror up on the first shutter press, then open the shutter on the second. Waiting a little in the time between will give time for the vibrations to die-down.

Honestly I think your worst problem is diffraction. Lighten up on it and come back to the world of f-stops below f/16. Looks like the lens is sharpest around f/8 (like many lenses).
 
Ditto what they said on aperture, gotta be in the "who cares" range or f8-f11
 
Go into your Custom funct. menu, turn mirror lock up on, Press the shutter onece (with the remote) to lift the mirror, then press the shutter again about 1 seconds later, This reduces movement in the camera body thus removing the shake,

f22 is too high... its kinda like if you went in the sea, you start swimming from a shallow end, Then it starts to get really deep eventually, but you keep going, it will start getting shallow again.

as ^ said, Stay at f16, no more..

some lens' have certain sweet spots for sharp DOF (at this close you dont need a high Aperture either... f/8 - f/11 would do this...)
usually the sweet spot is about 2 stops up from your max aperture meaning if your max aperture (like my 50mm ii) is f1.8, put your aperture at about f2.8 / f4 for a sharp image

Checklist:

Use a good tripod
use a Wireless shutter release
Turn mirror lockup on
Turn IS or VR off for still objects
use your lowest ISO setting.
use the best glass you have!

It may also be to do with the focusing of the lens...
If you have live view function, turn it on and zoom in to x10 or its highest zoom (this is a digital zoom = lower IQ)
this is just to check that you have focused properly, although your using AF it might still be off a little! so just focus with af then turn to MF and re-adjust as necessary.
 
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excellent tips, thanks guys! i use wireless remote, one of my favourite "toys". so nice not to have to touch the cam while shooting.

the reason i (used to) shoot such high f/stop was because often i take pictures for study, so art and appeal is not important, but having great detail is essential. but now that you guys helped me out with the whole diffraction bit, i think i get the general idea, enough to practice a bit and hit the books :) thanks for that!

So my goal is to have as much of the image in focus and detailed, you say f/16 is tops. what about for other situations, say 100mm or even 20mm? would the diffraction then be changed a bit due to angles? sorry i am still a bit fuzzy in this area lol.

last question. mirror lock up, just learned about this as well. is all it does is make a 2 step (press) method? is there any reason not to leave this on all the time? i know for well lit situations it may not be needed, but is there anything wrong with leaving it on aside from convenience?

thanks again.
 
Well for mirror lockup its a good method for a static camera and subject, but if either is moving (handheld or moving subject) then in the time between lifting the mirror and the second pressing of the shutter the subject could very easily move out of frame or the camera move out of focus (AF will also be off when the mirror flips up). Also its desigend to counter micro movements - if your holding your camera your going to get those movements just from your natural body movement.

As for getting more depth of field f16 is a rough ballpark figure that applies to pretty much all lenses (I am sure there are exceptions to this rough rule with some performing better and others worse). And in general its also the upper limit - myself I prefer to operate mainly in f13 for macro.

However depth of field is always limited, but there is a trick - focus stacking. That is you take a series of shots using a camera on a tripod with a focusing rail - keeping the focus in a fixed position, but moving the camera and lens closer to the subject for each shot - getting a bit of depth over the whole image in stages (making sure there is some overlap). Then you can either work on stacking the shots manually in editing with layers and layermaskes (urgh takes for ever if you do more the 2 shots) or better you can use a program (free) like Combine ZM *Updated now to Combine ZP I belive* to stack all the shots into a single composite image.

The great thing is from my experiments in this, is that you get great sharpness and very little noise through this process - and it gives you such a deeper depth than you would otherwise be able to get
 
last question. mirror lock up, just learned about this as well. is all it does is make a 2 step (press) method? is there any reason not to leave this on all the time? i know for well lit situations it may not be needed, but is there anything wrong with leaving it on aside from convenience?

thanks again.

It gets annoying having to press twice, you only really need it for tripod work so you get the sharpest image your camera is capable of
if you dontm ind pressing twice (although it will have no effect if your holding the camera therefore useless. then use it all you want)
 
Agree with the above posters. Mirror lock-up, be sure and use a tripod. Remote triggers are also helpful. I also find that unless you have the higher end glass (L or something very close), most zoom lenses are not very sharp at the upper end of the zoom. Keep your ISO low. Shutter speed at least 1/30 or better and get in the sweet aperture zone of your lens. You need to shoot some test shots with that lens to find out if it is 5.6, 8, 11, 16, or whatever. I would bet on that lens being in the 5.6-8 range. One other thing to do is to add light. Even if it is just for fill, you can then use shutter speeds and apertures that you want. Most of all, keep on shooting. Shooting good macro shots takes lots and lots of practice.
 
so playing around a bit (i need to get a test sheet to shoot on to learn it properly i think..?). i took it out and loaded up EOS utility. i got it all setup and took about 30 pics with VERY slight focusing changes, this was the best. i ditched the tripod and held the camera down on a 200 pound table and put some weight on it so it wouldn't budge a micrometer. also used mirror lockup and used the computer to take the shots.

i can only think of 2 things....the light is too poor...but thought the slow shutter speed would compensate? or the lens is really that bad,.....but i think its probably on the users end, not the lens lol.

here is the best result i could muster :(
letters are 49x15mm taken 3.5 meters away (10feet?)

shutter speed 1 second (i know that aint good, but the camera was rock solid....still a problem?)
f/6.3
300mm (testing the maximum range)
iso-100

sampo.jpg


any thoughts?


EDIT
gave it another try today in the sunshine.

is this all i can expect from the lens? or should it be able to preform better?
1/125sec
f/13 (i ran from 5.6-22 and this seemed best i think)
300mm
iso-100
on tripod with remote and mirror lockup.

here is a shot of an entire areole on a cactus with all its spines. had to resize for internet
spines.jpg


little more cropped and sized
spines2.jpg


here is the most in focus part cropped and not resized.
spines3.jpg
 
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