Moth with light reflected in it's eyes - why?.

[brianholland]

My wife has been trying out her new toy a ringflash, trying to photograph moths.
This one I think is a Silver Y but as you can see it has light reflecting in it's eyes - something that has not happened with other moths taken from a similar angle.

Does it suggest a trick of the camera or a more complex eye in this moth.

However how can she overcome this problem please and please keep any advice very simple as we are elderly and unfamiliar with technical terms. with computers or careras?.

Thank you,

Brian.

[Rob Chace]

I would suggest that you need to move the flash away from the axis of the lens. Most red eye/ eye shine type situations can be avoided by doing this.
Regards
Rob

www.lnrwildphoto.co.uk

[ChrisR]

Hi Brian, What you are experiencing is the same effect as when you see "cat's eyes" on the road. Cat's eyes bounce light back roughly in the direction it came and an insects eye is a 'compound', multi-faceted structure - basically it looks like a lot of tiny cat's eyes glued together in a rough hemisphere shape.

So the ring-flash is mounted around the lens and sends out a pulse of light towards the moth ... when it hits the moth's eyes the light travels down the facets that are facing towards the flash and the light bounces back out again towards the lens/ring-flash - giving that strange glowing look. But it just ricochets off the facets that point away from the flash and they appear brown.

As Rob said, the only way to avoid this is to mount the flash to the side of the lens so that the bounced flash-light doesn't come back into the lens.

[nutmeg]

Good advice from Chris and Rob.

When I'm running my MV trap often the first thing I'll see of an approaching moth is the glowing eyes.

[brianholland]

Originally Posted by Rob Chace

I would suggest that you need to move the flash away from the axis of the lens. Most red eye/ eye shine type situations can be avoided by doing this.
Regards
Rob

l & r wildphoto

Thanks Rob, Will pss this information on to my wife who will be interested in the suggestion.

Brian.

[brianholland]

Originally Posted by ChrisR

Hi Brian, What you are experiencing is the same effect as when you see "cat's eyes" on the road. Cat's eyes bounce light back roughly in the direction it came and an insects eye is a 'compound', multi-faceted structure - basically it looks like a lot of tiny cat's eyes glued together in a rough hemisphere shape.

So the ring-flash is mounted around the lens and sends out a pulse of light towards the moth ... when it hits the moth's eyes the light travels down the facets that are facing towards the flash and the light bounces back out again towards the lens/ring-flash - giving that strange glowing look. But it just ricochets off the facets that point away from the flash and they appear brown.

As Rob said, the only way to avoid this is to mount the flash to the side of the lens so that the bounced flash-light doesn't come back into the lens.

Thank you so much for this confirmation.

We wil be eager to try it out next time we use the moth trap.

Brian.

[Meta menardi]

AS spiders have simple and not compound eyes, they show this effect very clearly.

[brianholland]

I thank you all for takig the trouble to help us.

We will be setting the moth trap later this week weather permitting so will try out your suggestions then

Brian.

[Geoff F]

There is an article on using flash here Camera Flash: Appearance which explains all aspects of flash use and problems. Although it does go into quite a lot of the technical aspects there are a lot of tips there.

[brianholland]

Originally Posted by Geoff F

There is an article on using flash here Camera Flash: Appearance which explains all aspects of flash use and problems. Although it does go into quite a lot of the technical aspects there are a lot of tips there.

Thanks Geoff - will give it a go.

Brian.