Achieving focus

[Andy.bn]

Hi Pete & colleagues,

I guess I would like to ask your advice. At the end of May, after deliberation and advice, some of which was gladly received from this forum, I purchased my 1st digital SLR, this is a Canon 450D with a Sigma 105mm macro lens, and a monopod which I wish to use mainly for butterfly & moth photography. The main difficulty so far seems to be with focussing. I can’t get anything like a whole insect in crisp focus, maybe about half the beast on average. If the subject is side on and all at the same ‘depth’ then the result can be better. I am aware that some of these macro lenses have a small sweet spot of focus, and occasionally this is evident in other people’s shots that I see, but it shouldn’t be to this degree.

Whether manual or auto focussing doesn’t seem to make a difference.

Could a solution be that I need to use a higher F no. for a greater depth of field, such as f5 and above, instead of f2.8 or f3.5?

Do I need to be closer/further from the subject?

Or change the camera’s focussing mode?

Perhaps some of it is camera shake, but I know mostly the problem is focussing.

I would appreciate any help.

Best regards, Andy Bolton.

P.S.(Pete, I could put in a good example photo, but the system won't allow it.)

[Pete Eeles]

Hi Andy,

The answer to your question is the subject of entire books - so let me give a condensed version from what I've learned (especially from others on this forum, who I'm sure will "chip in").

First off - photography is a combination of science and art - one of the main reasons I enjoy it so much! My response here will focus on the science because the "artistic" side of photography is not only "in the eye of the beholder" - but there are also much better photographers on these forums that excel in this space. Gwenhwyfar (Lisa) has been an inspiration for me for quite some time - just take a look at her competition entries and you'll see what I mean.

As for the science - there are a whole bunch of factors at play here - and achieving the right "balance" is the key because there is no "single" right answer. For example - sometimes you want a small depth-of-field in order to ensure you have an out-of-focus background. On other occasions, if a "messy" background isn't an issue, then you might want a large depth-of-field (as in your example) in order to ensure that most of the butterfly is in focus.

So - with regard to the latter (since this is your question!). To maximise the depth-of-field there are two main approaches. The first is to take a shot further away from the subject, and then crop it in software. Although I do this with most of my shots, you do need to be careful not to stand too far back since you're losing pixels!

But the main factor in increasing depth-of-field is to use a smaller aperture (this isn't intuitive - but the maths work out - so take my word for it!). Now - having a small aperture itself is a major problem since it decreases the amount of light hitting the sensor. In order to balance this - you need to somehow compensate. This can be achieved 2 main ways:

1. Use a slower shutter speed. Since you're using a slower shutter speed you then need to think about either a) using flash (to increase the amount of light hitting the sensor) or b) using a tripod. In my experience - that latter is preferred. Flash is known to cause unnatural-looking shots.

2. Use a higher ISO setting. This increases the sensitivity of the sensor. However (and there's always a "however"), this increases the amount of "grain" in the picture too.

"I could put in a good example photo, but the system won't allow it."
You should be able to add an attachment to any post (click the "Upload attachment" tab below the edit window).

Hope this helps!

Cheers,

- Pete

[Rogerdodge]

Andy
Good choices - and welcome to the Canonista....
You have made some really good questions here, and I would like to have a stab at answering some, and offering a bit of advice if I may?
Firstly, moving from a compact to a DSLR is a bit like moving from a saloon car to an F1. I don’t know if you saw the Top Gear episode where Hammond took an F1 car round a circuit. Here is a bloke at home in McLarens, Ferraris and Zondas. Yet he couldn’t even get it off the line, let alone around a lap.
Given time and practise he would have been able to lap pretty quickly – but it is that steep initial learning curve that is the problem.
Now, the big subject to grasp is Depth of Field (or Focus) or DoF. This is the area in front of, and behind the focus point that is acceptably in focus.
The larger the aperture (2.8, 3.5 etc) the shallower the DoF, the smaller the aperture (16, 22, 32 etc) the deeper the DoF.
The nearer the camera the subject the shallower the Dof, the further from the camera the deeper the DoF.
The (not so) secrets are-
1/ Get the wings parallel to the film plane
2/ Use larger f No.s – rarely lower than f8. To achieve this-
3/ Use higher ISOs try 400+, your camera will deliver these with very little noise.
4/ Use a monopod or tripod to minimise camera movement.
5/ Don’t “fill the frame”, be a bit arty and include the perch, surrounding greenery etc.
6/ Use manual focus and “rock” the camera in and out of focus taking LOTS of photos – one will be sharp.
7/Practice, practice, practice – digital pictures cost nothing. You may wear out your “delete” button, but you will improve.
8/ Look at the pictures on this site from the really good photographers – study the composition – see how being a little off centre is good, how having foliage etc. draw an eye into the subject works.
9/ Forget sunny days. The best photographs are rarely taken on sunny days – the light is too contrasty, the shadows are too harsh, the butterflies are too skittish.
10/ It’s cloudy – let’s go take that winning photograph.
11/ Avoid flash – it is tempting as an easy way to get big f stops, but, it can look very artificial, as butterfly wing scales rarely reflect flash nicely.
12/ Use a lens hood – flare can soften an image
13/ Did I mention practise?

Settings-
AV at f8 – stop down to 11 or 16 if conditions are good
ISO 400
Manual Focus
2/3rds of a stop underexposed to start and then bracket exposures (ask if you want an explanation of how to do this simply) with very light or dark butterflies
Hi Speed shooting.
Turn the Beep off – it frightens some butterflies
Partial Metering
Auto White Balance

Pete will suggest shooting RAW, but I say JPEG until you are really happy with your results.

Good luck, and have fun – that is what it is all about after all.

Roger

[Pete Eeles]

Pete will suggest shooting RAW, but I say JPEG until you are really happy with your results.

Aside from agreeing with everything Roger has said (which is a first, I'm sure, ) - I just need to qualify this one comment. I wrote an article for the Spring 2009 BC magazine where I've said "no amount of digital manipulation can bring an out-of-focus picture into focus and such manipulation should not be a substitute for poor photographic technique".

On those grounds - I also agree that "getting things right" using JPEG is the best approach when getting your technique sorted. I took this approach myself a few years back and some of my best shots were taken with JPEG! For me, RAW simply gives you the ultimate control in "refinement" (and I mean REFINEMENT!!!) to get the image "just right". It is not a substitute for getting the basics right!

Cheers,

- Pete

[Gruditch]

Hi Andy, Very good advise from Pete and Roger, apart from the Gwenhwyfar (Lisa) bit, by Pete.

Use higher ISOs try 400+, your camera will deliver these with very little noise.

With a 450D, I'm not too sure what ISO you will get away with. On the 40D, which has a 10mp sensor, 400+ ISO, is no problem, however on the 50D, ISO 400 can be noisy. So with the 450D, having a 12.2 mp sensor, I doubt you can go too crazy.


Some people still using the older models, will often say forget the viewing screen, turn it off. But on the later models, like the 450D, the viewing screen are very good. Use it to check if your images are too dark/light etc, and adjust accordingly.

Gruditch

[eccles]

My Sony A700 also has a 12.2 mp sensor and noise is very well controlled, particularly with the latest firmware. I frequently use iso 400 as a starting point, dropping down to 200 if light permits, or stepping up to 800 if light is lower, although any higher than 800 will often need some noise reduction. According to Dpreview the 450D has good high iso performance so I wouldn't expect using the same with this model to be a problem.

[Gruditch]

ISO 400 a starting point Maybe it's just me, but I find noise in an image, unacceptable.
At ISO 800, especially in a macro shot with a diffused background, you will get noise.

Gruditch

[Rogerdodge]

Oooooops - duplicate post

[Rogerdodge]

Andy
You have had some good tips here, and we all (mostly) agree - how about that!!!
One last thing - the butterfly photographers worst enemy is the wind.
Remember that we are trying to capture the subject in the middle of the DoF, which is measured in millimeters.
If your subject is moving in only a mild breeze, it will be moving horribly in and out of focus. You can try to avoid this by using the machine gun method - firing off lots of shots in the hopes that one will be in focus.
You can also reduce the effect by getting an accompice to block the wind somehow - a coat, or, with really confiding butterflies, even hands cupped around it.
The other top tip is that most good butterfly photographs are taken early in the morning or in the evening. This is for two reasons. Firstly, the light can be faulous - a lovely colour, and diffused by virtue of travelling through more atmosphere. Also, a it is cooler, the subjects are less active.
This means you can get closer, and can take more time and consideration with composition, technique etc.
You will also find that the wind tends to be lower in the morning or evening (but not always).
The downside is they are harder to find .
I really hope all this advice will help you get the photographs you want to see.
Roger

[eccles]

Further about noise. I respect Gary's viewpoint, particularly since the quality of his photography speaks volumes, but I do think that sometimes people can pixel peek a bit too much. The designation 'digital' for a DSLR is an oxymoron since all sensors are analogue, and as a result will always have a certain amount of noise. It's whether such noise is noticeable in a print of normal dimensions, and if it is, whether it is objectionable.
The attached photo is a 100% crop taken last Saturday with my A700 and Minolta 100mm macro. ISO is 400. In other words, Andy, it is a cropped portion of the full size image viewed at pixel level. It is a straight transfer from raw using ACR with the NR sliders set to zero, i.e. no colour or luminance noise reduction. Sharpening was left at the default 25%, so in fact noise appears a little worse than it actually is. If you click on the image below, you can get a full size view of the cropped portion.
Unless the final photo is heavily cropped before printing, this sort of noise won't even show in the print yet alone be objectionable. Setting colour and chroma NR in ACR to around 10% will reduce this to (IMO) negligible levels. It is my belief that with good glass the Canon 450D will perform in a similar manner. It is after all, a very good camera.
In any case, Andy, don't take our word for it - try it! If you don't like the results change the settings back.
Cheers,
Mike.
P.S. I agree about the wind. It can be a real pain, especially since butterflies insist on sitting on the wobbliest flowers they can find.

[Rogerdodge]

- try it! If you don't like the results change the settings back.

Mike
This is one of the wisest things you have said, and you have said some pretty wise things.
This is the delight of digital - you can muck about with settings to your hearts content, quickly see the results, and delete anything that doesn't work.
But - what you will be doing is learning and improving.

Have fun

[Pete Eeles]

I agree with the "try it" bit! I moved from ISO 200 to ISO 400 as my default and, to be honest, found that my pictures were too grainy, for me - and have therefore reverted back. But Mike obviously has a different experience. So - definitely experiment!

Cheers,

- Pete

[Dave McCormick]

P.S. I agree about the wind. It can be a real pain, especially since butterflies insist on sitting on the wobbliest flowers they can find.

Yes, I have found this to be quite a problem, especially thse on grass stems. You set up your shot, it looks great, a woosh, a breeze sets it off.

I usually shoot 400 ISO and go down to 200 or even 100 given the weather. I'd only go higher at night. I am not sure why you'd need higher than ISO 1600 which some cameras can now go higher. I have had little problems with shooting at 400, sometimes I notice my shots look a bit grainy, so I can say 200 would be better. Technically he is now ISO should be used IMO:

ISO 50/100/200 = Sunny weather
ISO 400 = Cloudy weather
ISO 800/1600 = Night

I sometimes sharpen my images on computer, but this does create more noise sometimes, but then you can reduce noise (not sure if you can on photoshop but Paint.net has a function that says "reduce noise") it softens up the image depending on how strong you want the noise reduced. its not always good as it can soften up image too much, but if you have a grainy image, it can be ok to use.

Latley I have used my monopod more, its good for areas that are awkard to use a tripod and to get who butterfly in focus a higher Apature value is usually good, but anything over 22 then you'll get more of the background in focus too, and for better shots, you won't always want that. I had the oppourtunity to shoot a small toroiseshell today in various modes and times/AV values as it just sat there and let me shoot away. But if you cant do that, most cases you cant, try focusing on a flower and shooting different modes and times until you get an image you like, if you can get a good flower, a butterfly won't be too much harder to get, but you need to take into account that a butterfly does not remain stationary like a flower does I have taken photos of thistle heads to get them in focus and the background right too, so when I see a butterfly on it, I can do similar as the shot would be just the same with the butterfly, but your attention would be on the butterfly.

[Andy.bn]

Thank you all for so many comments, and so quickly! Pete and Rogerdodge especially. I understand a lot of what you are saying and it makes sense. Three points in particular: Try and be a little further from the subject.
Use the higher f numbers
Raise the ISO to keep the shutter speed up.
I believe that using Aperture Priority is the norm, does anyone experiment with other modes? Can anyone suggest their typical ideal shutter speed?
Rogerdodge, I have already printed out your comprehensive check list for reference. Interesting that you should choose Auto White Balance, I had always used 'Sun' for sunny and 'Cloud' for cloudy, so I will try this.

Andy.

[Shirley Roulston]

I also have appreciated this advice and raised the iso and stood further back and it indeed is based on loads of practise.
Thanks Roger, Pete and Eccles for explaining the above.
Shirley

[Chris Pickford]

....It is worth adding that, once practice has made perfect using .jpegs, it may be a good idea switching to .raw files as I believe most people find that the noise can be less evident when a raw file has been converted using a decent software programme (eg Photoshop or Elements), rather than by using the in-camera system which applies when jpegs are taken.

Certainly, when I compare noise levels using a D300 - I'm clearly not a Canonista ( or should it be Canonisto) at ISO 800, smoothed and filtered in Elements 5, with similar images shot a few years ago on earlier generation equipment and software, the results are signifcantly better. As for comparisons with ISO 800 tranny film, well....(it's grain rather than "noise" of course, but the effects are the same for purists)!

Chris

[Bill S]

Thank you all for so many comments, and so quickly! Pete and Rogerdodge especially. I understand a lot of what you are saying and it makes sense. Three points in particular: Try and be a little further from the subject.
Use the higher f numbers
Raise the ISO to keep the shutter speed up.
I believe that using Aperture Priority is the norm, does anyone experiment with other modes? Can anyone suggest their typical ideal shutter speed?
Rogerdodge, I have already printed out your comprehensive check list for reference. Interesting that you should choose Auto White Balance, I had always used 'Sun' for sunny and 'Cloud' for cloudy, so I will try this.

Andy.

I'm only a DSLR beginner but had a wet film SLR a long time ago. All the above is good, sound advice. I'd add that it's worth getting into the habit of checking the histogram after taking an exposure, it can help you get a feel for over/under exposure. In fact I had just started using the in camera "highlight overexposure" feature which makes blown areas flash when reviewing pictures on the camera's LCD.

I always used aperture mode until the photography workshop earlier in the year, where Pete described using speed priority mode. I think this is a sensible approach, I wander with my lens on autofocus and in speed priority with the speed set probably at 1/250 with my Sigma 150 lens. (I forget without looking at my notes but there is a 1.5 rule for shutter speed, i.e. use 1.5 the focal length). If I come across a butterfly I want to photgraph as a record, I know I will get a camera shake free picture. But if the butterfly has rested and looks settled enough for me to get a closer/tripod/different angle picture, I will set the lens to manual and switch to aperture mode so that I can control the DOF/detail in the picture better than in speed priority mode. Does that make sense?

Whether you choose AWB or a pre-defined setting for sunny or cloudy may depend of whether you are taking in RAW or JPG. I've found that RAW offers more easy post capture adjustment of the white balance so AWB works fine, but for JPGs it may be that choosing a preset option is the easiest way to manage the white balance.

Hope this helps

Bill