Product DOF control

[Phil Wood]

I am doing product photography and can not get a wide enough DOF working close up with rings etc even shooting down to f32. to get the whole product in focus Has anyone had success in this field that they would be happy to share. I am led to believe that the canon TS-E 90mm lens may do the trick . I have the onone software but find it grand for increasing blur but not the reverse. Thanks Phil

 

[Carter64]

Hi Phil,
Have you looked into focus-stacking? Not a technique I've used in practice myself (yet) tbf, but for static subjects in a controlled environment, might be worth a look?
Magic Lantern firmware also has a utility to semi-automate for this but again, sorry, I've no personal experience.

 

[Andy_S]

Does the final image useage require full resolution shots for large scale printing or would smaller files be sufficiant?
If so you could back off a bit and increase your working distance to gain a greater depth of field. Then crop down to what is needed.
Even filling 1/4 frame on the 5Dmk1 will give a 3Mp image, plenty large enough for web and catalogue shots.

 

[Phil Wood]

Thanks Mike I have experience of stacking but has been very time consuming but I will look into the Magic Lantern option you suggest.
Thanks Andy I find your comments very interesting and will do some experimenting as I do not need very large images but have been striving to get the best clarity and my natural inclination has been to frame tightly in camera. I will post here how I get on.

 

[specialman]

Does the final image useage require full resolution shots for large scale printing or would smaller files be sufficiant?
If so you could back off a bit and increase your working distance to gain a greater depth of field. Then crop down to what is needed.
Even filling 1/4 frame on the 5Dmk1 will give a 3Mp image, plenty large enough for web and catalogue shots.

I do this when shooting a collection of fishing flies that are different sizes and depths off the surface... backing off a tad really does help gain some DoF and the resulting crop is still good for A4 reproduction.

Glad someone else works like me

 

[Phil Wood]

I do this when shooting a collection of fishing flies that are different sizes and depths off the surface... backing off a tad really does help gain some DoF and the resulting crop is still good for A4 reproduction.

Glad someone else works like me

Thanks Pat will have a play tomorrow and post results on here.
Looks like I wont need to buy the expensive lens.

 

[Canon Bob]

I'm a little lost with the concept of backing off (less magnification) and then cropping it back in post......aren't we back where we started in terms of DoF?

Bob

 

[specialman]

Nikon 60mm macro lens and at f/6.3...

Focus point on the lower green fly in the middle of the body - sensor plane is probably 20cm above the flies:

Focus point on same position (on the body of the green fly) but this time I've raised the sensor plane by another 10cm and then made the appropriate crop in LR3:

The latter definitely looks to have the greater depth-of-field, leaving more fibres in the black flt sharp and not OOF as in the first shot.

Of course, there are ways round not having enough depth-of-field from the settings you're using - the already mentioned focus stacking and tilt/shift work. This is just one way to skin a cat and by no means perfect - it's just a quick way of working and a cheap fix. Using dedicated kit like a TS lens may ultimately be the best route .

 

[Phil Wood]

Thanks Pat you have definitely increased the sharp area.
Have you any positive ideas Bob how good is a tilt/shift lens the sharpness of gemstones is very important to me.

 

[Canon Bob]

The TS-E90 is probably as good as any macro lens and DoF control will give you what you need. The TS-E90 has a relatively high native magnification and also works very well with tubes behind it.....that would be my #1 choice for what you're trying to do but recommending TS lenses often seems to end up being contentious.

Bob

 

[Andy_S]

I do this when shooting a collection of fishing flies that are different sizes and depths off the surface... backing off a tad really does help gain some DoF and the resulting crop is still good for A4 reproduction.

Glad someone else works like me

Not had to do it myself, just though about it while reading the OP

I'm a little lost with the concept of backing off (less magnification) and then cropping it back in post......aren't we back where we started in terms of DoF?

Bob

Increasing the distance (reducing the magnification) will give a greater depth of field across your subject. Cropping does not change what's left in the image, it will still have the greater depth of field compared to increasing the magnification (it's not being magnified, just cropping the image).
If you crop to the same field of view, you'll still have as much in shot but at a lower resolution and different perspective (Greater camera-subject distance, less close up distortion).

 

[Canon Bob]

Increasing the distance (reducing the magnification) will give a greater depth of field across your subject.

Agreed

Cropping does not change what's left in the image, it will still have the greater depth of field compared to increasing the magnification (it's not being magnified, just cropping the image).

Agreed

If you crop to the same field of view, you'll still have as much in shot but at a lower resolution.

Agreed

....and different perspective (Greater camera-subject distance, less close up distortion).

Not part of the big picture and will only serve to add confusion

So,everything is spot on what you say except that we now have a smaller image. As soon as we display it the same size as the original, we've lost the advantage of using the lens at lower magnification.

Bob

 

[specialman]

So,everything is spot on what you say except that we now have a smaller image. As soon as we display it the same size as the original, we've lost the advantage of using the lens at lower magnification.

The smaller image (pixel) size is the obvious downside of this. But it's a case of balancing now much depth of field you require against how big the image will be reproduced.

I tend to back off in relation to how I know the image is going to be used; if it's going into a 5x5cm panel then I couldn't care less how much actual image space the object takes up - so long as the crop doesn't have to be upsized to the panel I'm cool. If it's destined for a DPS then there's only a certain amount of cropping back in you can do before you have to rely on interpolation to get the image back up to 300ppi DPS print size (4200mm plus bleed)

 

[HoppyUK]

Just on the 'backing off' technique, if you move back or zoom back and reduce the image area to half (effectively a 1.4x crop) you gain one stop of DoF. If you reduce to a quarter (2x crop, same as M4/3rds format) you gain two stops.

 

[EdBray]

Just to say that if the OP is contemplating a TS-e lens he may be better off buying a Mirex tilt/shift adapter and using either Mamiya 645 (manual) or Hasselblad V system lenses.

Personally I would go with the Mamiya option unless Hasselblad V series lenses are already owned, and also I would go with the T mount version as it can then be used on other manufacturers cameras.

A Mirex TS adapter is about £400, the Mamiya 80mm can be found for under £120 the 35mm for just over £150. which will give nice pair of lenses for less than the price of a single TS-e

 

[Phil Wood]

Thanks all now I need to experiment with moving the camera back and cropping to see if results are good.
Also Bob I would like your views on which is the most suitable TS-E lens for my purposes as I am using a 60D (crop sensor) and I do like the live view and the 90 seems a bit long
My workflow demands that I am quick as I have to produce about 120 images a day for the online catalogue.

 

[Canon Bob]

What are your minimum and maximum frame sizes Phil?

Bob

 

[Phil Wood]

Thanks Bob
The size I give to the client is 1024px longest side This is for online and printed catalogue
I work for an Auction house doing jewellery and ceramic items up to 20 cm square in a 60cm light tent. For larger items I have a 2 metre cube tent which I light as required from the outside. I am at present using my 24-105L in the big tent and sigma 70 macro in the small tent. I find the sigma very sharp especially at f8 but this is where I struggle with the DoF.
My smallest objects I suppose are diamond earrings about 6mm in size.

 

[Canon Bob]

I think the 90mm will cover your subject sizes better than the 45mm. The 20cmx20cm stuff is very much in the territory of the 45 but when going down to 6mm subjects then you'll need the potential increase in magnification that the 90 can provide with a 25mm tube behind it.
Some figures for perusal (full frame body);

All figures are at MFD for the TS-E90
The lens alone has a native magnification of a little under 0.3x at MFD (500mm) giving you a frame of 115x80mm.
Add a 12mm tube and magnification increases to 0.43x framing 80x55mm.
Add a 25mm tube and you get 0.6x and a 57x40mm frame.....the minimum magnification is now 0.3x and you can't frame more than 115x80mm when focussed at infinity (ie, the tube can't be left in place for bigger objects).

Hope that all helps a little.

Bob