Summary Large Image : Some of the images are not shown up


#1

I have integrated Twitter Summary Large Image.

https://twitter.com/crikey_news

Some of the tweets have images but some didnt show the image. The robots file of the domain from which the images are served allows "twitterbot "
There is no error on the Validator. The image sizes are larger than the minimum size , but still some of the images are not shown ?

Below is the URL which has image and all meta tags in place. But the image is not shown on twitter summard card


http://media.crikey.com.au/wp-content/uploads/2014/01/target.jpg (Image size is larger than the minimum size)

Can anyone let me know why ? Appreciate some help.

Thanks in Advance!!

Regards,
Moogy.