Experimenting with f-stops

When using a macro lens it is vital to have an understanding of f-stops.  If I left my camera on the automatic setting it would always pick f/2.8 or f/5.0 when I'm taking macro images.  The f-stop will determine the aperture.  The aperture determines how much light enters the sensor on the camera.  The smaller the f-stop number the larger the aperture so the more light hits the sensor.  Alternatively the larger the f-stop the less light will enter the camera.  With larger f-stops the shutter speed is slower so a tripod may be necessary, increased noise may also arise leaving images looking grainy.

For the following images of an asiatic lily, I had the camera on the AV setting.  I fixed the ISO to 200 and changed the f-stop.  The camera determined exposure automatically.

Here I used f/2.8, exposure 1/1000s, ISO 200

F/2.8 gives a minimal depth of field which results in the stigma being the only part which is in focus.

f/5.0, exposure 1/400s, ISO 200

Slightly more detail is starting to reveal.

f/13.0, exposure 1/50s, ISO 200

Now you can see the spots on the petals and more detail in the anthers.

f/25.0, exposure 1/13s, ISO 200

A larger depth of field is given showing the most detail.

Basic manual photo stacking in adobe photoshop elements

Focus stacking is one of the most useful tools for me in adobe photoshop CS5.  There is no in-built facility to do this in photoshop elements 9 but this is a tutorial on how I improvise.  For this to work, all photos must have all elements in the picture aligned.

I took two pictures of the same orchid.  The first has the front white part of the orchid in focus and the second has the red dots in the centre of the orchid in focus.

 

1. Edit both photographs in the RAW editor so the colours match.
2. Open both photos in photoshop elements
3. With the photo open which has the majority of the details which you want to keep from the menu choose select>all
4. Then from the menu edit>copy
5. Then open the window with the other image and from the menu edit>paste.  This pastes the first image over the second as a new layer.
6. Add a layer mask by clicking on the rectangle button with a white circle in the middle.

 7. When you paint the layer mask with black paint then you can remove the area of the image of the top layer.  If you've removed too much then using white paint will bring the area back.
8. When you've finished you can flatten the image.  From the menu Layer>flatten image.
9. If your happy with the result then save, but don't forget the change the file name.

This is the final image I achieved:

 You can see this image on my website: http://www.flower-pictures.co.uk/cut-flowers/hc84cf23#hc84cf23

Frosty morning

So, it is a long time since I posted anything, and that was not even a proper blog post; just an intro.  I won't let that happen again, and my next blog post will be much sooner.

It was a frosty Sunday morning, so I ventured out for a walk in the woods. I was feeling lazy, so I just put my 18-55mm lens on my camera.  I didn’t feel like carrying my macro lens and tripod, which I am normally never without.  I was so happy with my macro lens that I literally forgot about other lenses. 

The frost left everywhere looking magical.  Even the leaves and dead grasses seemed to come alive.  The ground was frozen solid, so every footstep was accompanied with a crunching sound.

http://www.flower-pictures.co.uk/leaf/h817bbd4#h817bbd4

The berries on the ivy, which were coated in frost looked almost good enough to eat.  They look like they'd been dipped in sugar!

http://www.flower-pictures.co.uk/leaf/h2e44ec90#h2e44ec90

I am not a landscape photographer, and don't even pretend to be.  I can't imagine getting up at four in the morning just for the possibility of getting a great shot.  The only thing that would make me get up at that time would be the chance to see a supernova, or the aurora.  The image below, is my attempt at a landscape photography.  It is not perfect but I like how the green gate contrasts with all the brown colours in the image.

 You can see more of my images at my website: www.flower-pictures.co.uk